I don’t have had the need for extra (purchased) add-ons. Mostly because I don’t know what they do or help me in the process. I like node-wrangler
, but didn’t know it existed until Michael. told us so.
For me it’s is not only knowing the ins and outs of Blender. But also how the process works. What make hard-surface works, how procedural textures technically work. If you understand that, than you can appreciate some add-ons. Because they save you a lot of work, or doing very technical stuff.
So I don’t use extra add-ons, besides the ones available in Blender. But I can imagine, for a professional, time is money. So get tools to make your work easier. But then I say, pay for Blender also, and become a member. See Blender development fund.
Personally I’m a bronze member. Because I find this piece of software excellent!