Thanks for the feedback, I appreciate that.
Your conclusions are pretty spot on with my own. I relied heavily on marketplace assets and optimizing them has been a royal pain. From getting the texture LODs right to finding all the hidden light sources (you'd be surprised where they turn up) I've realized that I'm an amateur trying to reconfigure the work of professionals and it's no small endeavor. On top of that, I used a framework (Horror Engine) that was really nice for streamlining things but only as long as you stay very well within the use case of it, which my project did not.
Going forward I'll work to rely less on the assets of others and optimize them immediately as I download them so I'm not backtracking. I am still a solo dev but I've been using AI to fill some of the gaps and it's working well. I'd love to have the funds to hire talent but... one step at a time.