I feel the same way. Not nearly the investment you have, but I now have all my welding stuff dialed in, ready to go, and enough practice that I understand the settings I need for the stuff I do ... and I've run out of projects.
I could weld up my
land plane but it works fine bolted so there's no need. I keep thinking I'll experiment with different angles so each blade feeds the next. but really the only deficiency is, it leaves an inch-tall berm along the sides and that's trivial, not worth cutting up its heavier gauge cross pieces (were snowplow blade spines) that I might eventually use for something more important.
If it won't go, chrome it! we used to say about hot rods. Maybe I should start painting all my old implements that I never got around to.