10g Tank Plan - I need your help

I see no reason why neons cannot be kept with a betta in a 10 gallon tank. Other possibilities are Ember tetras or Cherry barbs (NOT Rosy barbs). And the cories, of course. Gotta love the cories.
 
The white clouds like it cooler than the betta. Rainbows with long fins will probably have no fins after living with the betta.

I love ADFs. If your betta is peaceful then I would get one, but if it feels the need to establish territory don't get any, because ADFs are not respectful. When I had a Betta with ADFs it was constantly stressing because the ADFs would not leave its territory alone. Also, you have to make sure the betta doesn't get the ADF's food by handfeeding or feeding with a turkey baster.
 
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