Sorry, I haven't read any of the above inspiteful commentary.
here's my take.
Most good games are too long.
80 bucks Australian for a game, I'd really like to know I've done it at 40 hours or less.
Here's the big name games I've played through, and thought the length was about right
Terra nova (several times - actually this is due to be played again)
System Shock (the original-I'd play this again if Barry gives me the CD back)
Warcraft 2 (bit dull now)
Mechwarriors- 2 and 4 (was there a 3?)
HalfLife was brilliant except the last mission was stupidly hard and I gave up and I won't play it again
Syndicate was brilliant, the last mission was stupidly hard but I did it once, and I'll play it again but ignore the last msiiosn
UFO - I've played a couple of times quite a long way through, without really getting to the end. Quite happy to do it again from scratch, the early msiisons are much more fun.
Biggest playability award goes to Gunship 2000 - in squad mode, or railroad tycoon.