I build on 2' by 4' ceiling tiles.

Do I understand that you wish to jump from ARF's to scratch building and skip the kits ?

A kit or two will teach you a bunch. And a good kit even tells you what tools you will need.

25 years in this hobby, nearly 40 in modelling, and almost every year I run across some tool I can't live without .

The more tools you have, the more jams you can get out of, thats all.