Can you post a photo of the tank? That will help us give you ideas on what you can do with it. I like Betta-based community tanks and over the years have only had, maybe, 1% of Betta that didn't suit community life; and that is out of hundreds.
Do you have preferences for companion fish? I like Ember Tetra, Endler's Livebearers (males-only), Dwarf Panda Guppies (males only), smaller Rasbora like Chili, Merah, Mosquito, etc., Pygmy or Habrosus Cory. I love Neons but only house them with Plakats as I have found them the most nippy of the smaller Tetra. However, I have found shoals of 15-20 help keep the nipping within the shoal.
I have always suggested a minimum of six Nano fish in a shoal with more being better. However, not long ago I asked Rachel O'Leary (Msjinkzed on YouTube) about shoal size when housed with a predator and she said no fewer than 8-10 for the health and longevity of the Nano fish. So I have changed my advice. This is for mid-tank dwellers; not bottom.
No fish larger than a Betta in body, no skirted Tetra. It is best to avoid Gourami, especially larger ones, as they are labyrinth fish and will fight the Betta to the death over the same territory.
As you have a back-up you should be fine.
Almost forgot: As you are deciding, plug in to AqAdvisor - Intelligent Freshwater Tropical Fish Aquarium Stocking Calculator and Aquarium Tank/Filter Advisor