seems like you have a lot of bottom dwellers lol, i think 1 dwarf pleco is enough though, all of you peeps keep telling me they create a lot of waste, so i wouldnt add more than 1 pleco if i was going to add a lot more fish, my LFS has a clown plecos so i know ill be adding 1, as for the snails, i have chose nerite which ill be ordering 3 online ^_^ thats all my bottom dwellers for now hehe and of course, the star of the tank will either be 6 cherry barbs or a fighting fish ^_^
as for your otos, i dont really know what to say =P i know they are a very delicate fish, so i would personally stay away from them and just substitute them with another kind of algae eater