RE: Does size really matter?
My preference is the E-station chargers by Bantam.
It does it all. The one I have BC-5 balance charges lipos up to 5s, series charges lipos up to 5s (if you want to)
charges NiCad and NiMh 1 to 14 cells, charges my gell cell in my field box, 1 to 5 amp charge rate with peak detect. It has a probe available for temp cutoff, and a host of other programable features for $125.
Truth be told, if you look around there are a bunch of great chargers out there.
Not hard to program either. pick battery type, voltage and charge rate and go. It won't charge if you enter the wrong voltage so you can't make a mistake.