Threadfin rainbowfish - Iriatherina werneri
Spotted blue eye - Pseudomugil gertrudae
You could also consider the forktail blue eye (Psuedomugil furcatus, around 1.5in) but not the Pacific blue eye P. signifer as it gets to 2.5 in and is aggressive to conspecifics (although schooling) and needs space and brackish water.
Poecilocharax weitzmani (variants of spelling, because nobody can agree on it: Poecilochirax/poecilocharax, weitzmanni/weitzmani/weitzmanii) I don't know the common name, don't think it has one... special little tetra-ish thing.
Sparkling gourami - a good feature fish in a tank this small as it's safer to keep it alone
Heterandria formosa - dwarf livebearers.