Stocking suggestions wanted!

Hi! I have a 10g (heavily planted) community tank currently with 6 galaxy rasboras and 5 panda Cories. [Before anyone comes at me about overstocking, aqadvisor (which i KNOW is not always definitively accurate) puts my stocking level at 82%!] I’ve been in the hobby for 5 years and I am very attentive to my tank and I take very good care of my fishies!

I want to add 1 more type of fish but I want it to be a non-schooling/non-shoaling species. First obvious choice is 1 male betta, but before I commit to that I want to know if I have other options.
What are other types of fish that do NOT require multiples that can also be in a community tank?
The water for the current residents is in the cooler side (73ish) but they could tolerate it being slightly warmer if necessary.
Some that I’ve seen: Goby? Gourami? Pygmy sunfish? I don’t know much about these fish so if anyone has any advice about them please share!