Skippi you will love your clown Loaches and as you know I'm sure from all the discussion around the forum they should if at all possible be kept in groups of three or more, and in about a year you will need a larger tank

I have angels and larger neons in with mine so I think any of your neons would be fine. But I'm afraid any thing else on the bottom unless maybe a bristlenose or something like that to keep the tank clean later might cause territory wars, especially since the other loaches have already been in the tank. Clowns like lots of caves though they will swim at all levels eventually. just some thoughts

Carol