I have a project (X.509 certificate lifecycle manager for bootstrapping CAs, issuing certs, like Lemur or Vault PKI backend) I would like to provide this free f

I have a project (X.509 certificate lifecycle manager for bootstrapping CAs, issuing certs, like Lemur or Vault PKI backend) I would like to provide this free for any solo system administrators, small companies for internal use, software developers, freelancers, but I don't want to give the possibilities for big companies to repackage and resell it as their own and I also want to force them contributing back. What license should I choose and why? I thought GPL or AGPL, but I really don't want to scare away individuals and small teams (who this software would help the most).