That’s very smart! To go with what you know and going by an SRD saves a ton of development time. It sounds like this project was really meant to be. It’s good you have a group already because playtesting multiplayer TTRPGs is a nightmare for most people, especially when something is a homebrew. It allows for a lot of balancing and adjustments on the fly.
You should all be very proud of putting this together. Will you offer it on Drivethru RPG as well? I bet people would be interested.