She's not a noob... she's a professional!There's all kinds of options for something as small as a 10g. 10s are cheap and hoods, stands, hardware are easy to source. Like said, a male betta and some pygmy cories or nano fish. Some scarlet badis. A bunch of celestial pearl danios, a group of female bettas, etc... The list goes on. Would most of us suggest a 10g as a starter tank? Probably not. 20L and up.
and I was joking about not stopping. Personally I wouldn't do a 15, just because they're not that common, I'd go with a 20H, same footprint, and cheaper to get than a 15. all other accessories would be the same, except filter, and great deals can be had on filters.. so would be, IMO< the most cost effective way forward.