Well I have a 10g that's currently cycling and I've been thinking non-stop day and night all the possibilities to stock it. I too strive for variety and for as many different fish as possible. Here are my thoughts:
Tetras need to be in groups of at least 5. As do rasboras.
1 male guppy would be happy as a loner.
Cories need to be in groups of at least 3. Dwarf cories would mean more fish up top.
1 oto would be fantastic and not add to my bioload, as long as I can keep it alive.
A pair of cherry barbs would be nice.
A pair of killifish would be nice.
I really really want harlequin rasboras.
1-3 male Endlers would be great. They are very colorful, males get along (and don't get pregnant), and they are small.
No pleco. No German Blue Rams. Decided against a betta because I want a community and tank is too small for a sorority.
Have considered RCS, but not sure if fish will just eat them or the RCS will take over.
I decided that I would just have to go look at the lfs and see what's available and what speaks to me.
Here's what I would stock my 10g with if all fish were available to me:
3 harlequin rasboras, 5 galaxy rasboras, 3 pygmy cories and 1 oto (or RCS). As much as I despise the color red, I have fallen in love with red fish.
Therefore my advice to you: find the fish you love. Recognize the boundaries of your tank. You can push the inch/gallon rule just a little (by 1 or 2 fish) as long as you keep tank clean. With a 10g you really can't have too much variety. That's the reality of a 10g.
One other possibility I contemplated:
3 neons, 3 cardinal neons, 3 black neons, 3 green neons. (and maybe some ghost shrimp for clean-up) Sounds cool. And then get a moonlight and you've got a techno-tank. lol
