In previous answers in this thread you have expressed a preference for fast games and also a dislike for games that eliminate players 'with hours to play'. Are these two philosophies related?
They aren't.
Fast games are good because there are more opportunities to play them, players get more of a chance to win a game over the evening, and you get more variety of experiences over your evening.
Eliminating players with a substantial amount of game left is bad because you leave them with nothing to do. I guess it's getting kind of late. Maybe I'll just go home. It's fine in an online game, where I can just go off and start another game somewhere; it's awful for anything to be played at a kitchen table.
I obv. don't think player elimination is always bad; I think it's fine if there isn't much game left. It's entertaining seeing how things play out in Gauntlet of Fools, and doesn't take long. And the threat of elimination can be a fun thing. In Risk though, well, thanks for having me over. I'll see myself out.
Do you think any long game (let's say typically more than 1.5 hours per game) is destined to either have a fairly dull and meaningless early game or be forced to eliminate players early?
No.
Are there any 'long games' out there that you think successfully walk the fine line between giving players meaningful strategic choices all through the game, while at the same time keeping as many players as possible 'in contention' until the later stages?
Staying in contention isn't an issue. It has to be fun to lose! And if it is then it's okay not to be in contention. You can start a game of Scrabble knowing you have no chance of winning - the other player is just way better at anagramming than you. That doesn't stop you from having fun anagramming though. That would be true even if Scrabble took twice as long (although, being so homogeneous, it's just as well that it doesn't).
Some people may make games faster as a way to avoid eliminating players while minimizing how much time you spend knowing you've lost. I just make fast games because I like fast games.