Introduction and Warning
Look, I really, really don't want to talk about the Washington Nationals, understand? I wanted to make an attempt at selecting an all-time 25-man roster for the Expos, but only in the 1969-2004 period of purity (sometimes pure joy, often pure anguish) when they were in Montreal.
For this exercise I had to set some ground rules. I am only considering performance of players while they were Expos - not before or after. I'm looking only at players who played at least 100 games as Expos. Some of the similar efforts of others in the past (see "Other lists", below) consider players' entire careers - sensible, but not what I'm doing. Statistical references are, as usual, to baseball-reference.com.
The Starters
Tim Raines, LF
He needs to be in the HoF. Probably the best player in Expos history. Leads off for me - .391 OBP and 635 SB as an Expo. Not much more to be said.
Jose Vidro, 2B
For me, one of the more underrated of the Expos greats. Good 2B (and best Expos 2B by a large margin) who could do it all. In particular, I would bat him second on this team for a number of reasons: great bat handler, .367 OBP, and surprisingly the third best SLG on this squad after Guerrero and Dawson. Batting behind Raines would set up two switch-hitters at the top of the lineup - it is to dream.
Vladimir Guerrero, RF
Impossible to keep him out of this lineup. He played for the Expos during his prime (ages 21-28) and compiled .323/.390/.588 numbers. In addition, cannon for an arm.
Al Oliver, 1B
Only an Expo for two years (1982-1983) but one of the franchise's best hitters in history during that short time. .315/.370/.462, 105 walks to 103 strikeouts during the period. I would bat him cleanup against right-handers... maybe drop him down a bit against lefties, but he probably still plays. (In 1982 his splits were nearly as good against lefties as righties - not so much in 1983, or for his career overall.)
Andre Dawson, CF
The Hawk (and my brother's favourite player). 225 HR as an Expo and good speed, if we get him before the turf got to his knees.
Gary Carter, C
Hall of Famer, great defensive catcher, great handler of pitchers, and good power throughout his career.
Hubie Brooks, SS
Surprisingly good hitting and power but so-so defence. However, the offensive margin over his rivals is too great to keep him down.
Tim Wallach, 3B
Steady defensive 3B and consistent bat with occasional power. Not great in the OBP department (.317) which is why I bat him eighth, but he'll pop one occasionally and anchors the team. New member of the Canadian Baseball Hall of Fame in 2014.
The Bench
Larry Walker, OF
Walker really did have amazing stats as an Expo even before heading to the thin air of Colorado. Looking even at neutralized numbers for his 1989-1994 period, he was creating runs at a clip of 104 per 162 games. Not at all bad. I would consider platooning him with Guerrero if Vlad got a bit run down.
Rusty Staub, OF
All the talk about le grand orange was justified - he had a slugging average of almost .500 (.497) for his three seasons plus in Montreal, and was nearly six wins over replacement (5.9 oWAR per 650 PA). Another good left-handed bat to have.
Outfield really was the deepest position for the Expos. Raines, Guerrero, Dawson, Walker and Staub all richly deserve to make the team but I looked hard at Warren Cromartie, Ellis Valentine, Rondell White, Moises Alou and Ken Singleton (who showed flashes of his later excellence in Baltimore).
Bob Bailey, 3B-OF
This one surprised me. I expected this to be between Wallach and Larry Parrish, but Bailey's numbers from 1969-75 compare very favourably with both - highest SLG of the three and OBP that is more than 50 points higher than either of them at .368. I still have to have Wallach start looking at defence and the overall picture, but Bailey is clearly better offensively than Parrish and more or less even defensively.
Ron Fairly, 1B-OF
Another mild surprise. After Al Oliver, I looked at Andres Gallaraga and Tony Perez and expected one of them to outshine Fairly - but while Perez's pure offensive numbers are better, they're not that much better, and Fairly was the better fielder and all-round player. Gallaraga's best offensive years were ahead of him when he was in Montreal.
Mike Lansing, 2B
Ron Hunt and his legendary HBP gave him a gaudy .390 OBP, but his near-total lack of power and underwhelming defence make him less appealing to me than either Lansing or Delino DeShields. It was a close call between the two of them - both had excellent times in Montreal. DeShields had a better OBP but Lansing slightly better power and markedly better defence.
Orlando Cabrera, SS
I looked at a lot of shortstops: in addition to Brooks and Cabrera, Chris Speier, Wil Cordero, Spike Owen and Mark Grudzielanek. Brooks is demonstrably better as a hitter but had less than stellar defence. Chris Speier (a personal favourite of mine) was probably the best of the defenders, but unfortunately his offensive is so anemic (.245/.323/.332) that it's impossible to choose him. Cabrera provides not quite as much defence but a lot more offence, and played steady shortstop for seven years in Montreal, so is a worthy choice for backup shortstop.
Darrin Fletcher, C
After Gary Carter, the rest of the Expos' catchers are a collection of steady but unspectacular guys (but comparisons with a Hall of Famer are difficult anyway). Fletcher put in a lot of time at catcher (more than 500 games between 1992 and 1997) and held his own with the bat (.266 / .322 / .422).
The Starting Pitchers
Pedro Martinez, RHP
Only with the Expos at the very beginning of his career (ages 22-25) but dominant then. ERA+ of 139, more than three strikeouts per walk, and more strikeouts (843) than IP (797.1).
Steve Rogers, RHP
Expos all-time leader in wins (and losses), and a reliable workhorse pitcher who spent his whole career with the team, including some pretty bad years. Every time I remember Blue Monday I try to remember that he had a career playoff ERA of 0.98. Look it up.
Dennis Martinez, RHP
El Presidente deserves to be remembered for more than his perfect game - .581 winning percentage with the Expos between 1986 and 1993. Didn't get to the 'Spos until he was 32 and led the league in ERA at age 37. Exactly 100 wins as an Expo with only Rogers having more.
Jeff Fassero, LHP
Like most people, I forget how good he was when he started his career with the Expos (at the advanced age of 28). Average WAR of 3.5 / 162 games and ERA+ of 130 in a swing role (100 starts but 162 relief appearances).
Dustin Hermanson, RHP
It's narrow, but I think he beats out contenders like Bill Stoneman, Steve Renko and Javier Vazquez - in four years with the Expos he had 122 starts and compiled an ERA+ of 112 (better than any of the above) in a period when the team wasn't very good (four consecutive fourth-place finishes).
The Bullpen
John Wetteland, RHP
A dominant closer in his three years with the Expos - ERA+ of 170 and opposition OPS+ of only 60 (opponents got on base at a .280 clip and slugged only .297). 189 games, finished 159 of them and compiled 105 saves.
Jeff Reardon, RHP
Career Expo saves leader with 152 and a 2.84 ERA while he was there. Intimidating closer in his day.
Tim Burke, RHP
Another pitcher who always seemed to be there but whose numbers are surprisingly good on close inspection. Expos all-time leader in games pitched and ate a lot of innings, but was much more than a fill-in - gave up fewer than 8 hits per 9 innings during his time with the team and ended up with an ERA+ of 136. Interesting that in almost exactly 600 innings (600.1), he walked 189 batters but fully 65 of those were intentional - Buck Rodgers, qu'est-ce que c'est?
Mel Rojas, RHP
Continues the theme above. It didn't hurt to have connections to the Alous (nephew of Felipe, Jesus and Matty and cousin of Moises) but the performance was excellent too. ERA+ of 129 with the Expos (who got the best of him, because it was only 107 for his career), and had almost as many strikeouts as hits allowed (419 to 428, in 512.1 innings).
Bryn Smith, RHP
Another big, quiet righty who did good things. Started his career with the Expos as a reliever but became a reliable starter - WHIP of 1.179 for his time in Montreal and ERA+ of 111.
Honourable Mentions
While the early-franchise heroes Boots Day, Coco Laboy and John Boccabella won't get on many all-star teams, aren't they fun to list? Most people of a certain age will hear "Bocc--abella" on stadium announcements in their dreams forever. Ron LeFlore's 1980 season was so exciting with the 97 stolen bases, but he moved on (and not to better things). I really liked watching Rodney Scott and Doug Flynn at 2B, but looking now at their nearly non-existent offensive contribution it's amazing they could take the field as often as they did. Mike Marshall and Claude Raymond, from the early days, were a ton of fun to watch and consummate professionals too. Bill ("No-hitter") Stoneman wasn't the most consistent pitcher but had flashes of brilliance and went on to a great front-office career with the Angels.
Other lists
A number of other writers have made similar lists. A few are linked below.
Sports Illustrated / CNN ran a poll which got about 12,000 responses - results are here.