I tried gitea a while ago and it seemed very well featured while running much faster than gitlab. Single executable go app so it was also trivial to install.
I used both, and in my experience gitea/gogs starts out much faster than gitlab, but becomes slower and slower as repository sizes increase. At some point it became practically unusable, despite the repository not being particularly large.
On top of that we had constant issues with pull requests causing internal server errors, the merge check failing in mysterious ways, and so on. These issues may have been fixed now. We ended up switching to GitLab, and while it's quite resource intensive, performance seemed much more consistent.
