What logistics? They're the galactic race most used to living in cramped conditions and spending all their lives in a spaceship. They bring their own safety precautions (the suits) not to get sick from contact with other people. Their engineers know how to make use of every scrap to survive and get by. They can eat the same food as the Turians (who I don't think we're leaving behind, given they're one of the most powerful civilizations in the Milky Way).
I was talking about how to cryogenise them, I dont think the suit can sustain it (If someone has the proof I'm wrong, I'm interested), so you'll have to manage a lot of Quarians whitout their suits on, at the time of departure and arrival. Also how to preserve the whole quarians population when they'll be in close contact to others species for a long time (unlike on their ships) . There is the fact that they'll need more antibiotics and immuno-boosters than the others, They'll need extra clean rooms (ME Wiki) for them. They also cant reproduce at the same rate as the others, while not having the life span of a krogan.
So,
They are fragile, have no money, no authority or political power, they have difficulties whith their reproduction, BUT they're good at living in a spaceship so we should take them ?