mhmm, i totally saw some bumblebee gobies the other day, they are the CUTEST things ever. like, 1-2 cm long. and really relaxed. you could get quite a few in there.
i had a dwarf puffer in a 2.5, but it died. not for lack of space tho, unexplained phenomenon. course they claim 5 gallons for each dwarf, but really... just make sure it's well planted.