I tend not to use any addons, maybe a library here or there that would make my life easier. Producing everything yourself when you’re on a time crunch is not manageable.
I don’t like addons that make my life so much easier that it becomes a hindrance to me. One that fixes polygons sounds a bit too 2022. It’s good to go through the fire and flames and learn through trial by fire. After you’ve managed to know all the basics by heart, I believe it’s when you can take advantage of any addon out there. That doesn’t apply to everything though, there are topics that go so deep that I will not master in a lifetime and using an addon might be a good thing. So you have to pick and choose what is more convenient for you. But again, I suggest you try to master the basics.
You can take a deep dive through the Blender Market, see what addons are out there that interest you. They have filters for you only focus on the modeling ones for example.
