Welcome!
Back around 1980 just out of college I did three DIY kits, a pair of 6 cu. ft. transmission line bass cabinets, a Hafler DH-101 preamp, and a Hafler DH-200 power amp. Needed help with the preamp, except for the veneer (was very tight on schedule and had no experience in veneering) all were considered a success. But no way would I think about "inventing" anything like that. As advised the bass cabinets were overwhelmed my home (or any house I'd ever afford), but they were magnificent in a 20,000 cu. ft., 160 seat, chapel driven by a 20 wpc amp. That's one of the dangers of DIY, can't audition beforehand.
Resale value of DIY is another hazard, even for kits. Add to that no local dealer support. And the ever present proud papa syndrome. So DIY is for the adventurous. Good luck.