Cichlid people often talk them down, but, for a 10g, the fish with the most personality would have to be a betta. I love spending time with my 10g in my dorm because "Mo" always comes to greet me, and sometimes to be "pet" like a cat (well, much less vigorously, of course).
I gotta respect my cleaner team, though, my four Cories are hard workers, and they even do the job of Plecos with much less poop. (Today, they started eating the algae from my plastic plants.) My Oto (I had three, but "Methuselah" is the only one who hasn't died in the four months I've had them.) is constantly doing the Plec thing, and I have yet to have an algae outbreak since he and his two "sibs" enterred my tank.
All in all, I'd have to say that these are my favorite fish, especially since this is my first tank in probably 15 years.