I never really understand this complaint, especially as somebody who has actually ran my alt characters through the game. I mean ME1 had nearly no variation of events, almost nothing from ME1 had an effect on ME2's plot outside of Kaidan or Ash, and people merrily ran their alt characters through.
Now ME2 had a great deal of variation depending on what you did within that game, such as who you recruited and outcome of side missions and such - but so does ME3, especially post EC - you can basically wipe out the Geth and doom the Krogans to extinction should you so choose, a lot of how the ME2 squadmates perform during their quests (if they live or die) is a result of their loyalty from ME2.
ME3 was also the first time in the series that options were actually locked off to the player as a result of prior game decisions - for example, the best case scenario's for the Genophage and the G/Q war were locked off without proper conditions, Tali/Garrus are unavailable as romanceables, whether or not you can convince Ash/Kaidan to stand down is the result of a score part of which is tallied from ME1 actions and etc. Heck, you could be 2 men down if Garrus/Tali were dead and 3 if you managed to get Ash/Kaidan killed off as well.
I can get if people like Balthus feel burnt out, fair enough certainly it was a rather crazy 3-4 months, but I just never got this particular complaint especially now that the EC is out and we actually do get epilogues that are reflective of our playthroughs.
