How best to setup github repositories

Dear Experts,

I am looking for help and suggestions best practice for setup of your GitHub repo's.
Currently, my team has 1 central repository with multiple branches: master, release, hotfixes and features.

The team has expanded in size from a few people to 10 people and we've recently had a few events that have lead to merges being overwritten and lead to numerous discussions with the team on how they push code.

We have over 70 unique code objects to manage, each an executable that runs on the server from processes, reports, extracts and so on.
A recent idea I had was to break them up into logical feature groups such as:


If you were in my shoes how would you best approach?

Thank you in advance

Wayne