I think the only real problem I have with with ME is a problem I have a lot of modern games. The general idea of having way more potential party members than you can actually have in your party.
I tend to have favorites, and with little to no reason to actually bring along anyone but those favorites, pretty much everyone else was a bench warmer. I miss the days of RPGs like Baldur's Gate, where you'd have a genuine full party tagging along for missions, allowing for more complex party interaction as well as dynamic combat. That's just me I suppose though. I get that more characters isn't necessarily feasible with an action game like ME, but still.
As it is, I just took Tali and Garrus with me EVERYWHERE. My Space-Wife and my Space-Bro, I called them. We three were the only ones who really saved the galaxy. Everyone else just got credit by association. XD
Just my 2 cents.