Having been very deep down the open mold frame rabbit hole — 3 separate builds — I would recommend just getting a quality name brand frame set. Honestly, the monetary savings are not that great with an open mold frame, and if you factor in your time at all, it’s a losing proposition.
I learned a lot doing open mold frame builds, but I don’t see any compelling reason to go that route in the future. Just my $0.02.