If by small round bales you mean 4'x4' bales then it should work pretty good. I move that size bale with my
B3200 all the time. I wouldn't move any larger bales though, 4x5 are too big. Also note that kubota only offers their own version of a quick attach on the loader for this size tractor, so you would have to either build your own bale spear or get a skid steer style quick attach like ATI (then you could use a commonly available bale spear.)
Also note that the
B3300 doesn't have a mid-PTO and therefore can't run a mid-mount mower. You could run a bush hog or a rear-mount finishing mower however. If you do need a mid-mount mower you would need to go up to a
B3200 or
B3030.
Good luck on your purchase, I use my
B3200 a lot and it's been a great little tractor.