I'm generally happy with what I have, but I may treat myself to an Alpa 12TC.
I think the main thing would be to get into 4x5, and pay someone to handle the film loading and processing. He/she would give me loaded film holder, with a film of my choice it them. I would return the used holder to him/her, he would have them processed/scanning/printed at great/experienced lab, and return it all to me.
Time machine, definitely. Other than that, someone said a Leica 4x5. Absolutely agree. This would be a great thing. An actual precision-made 4x5 camera that was in perfect alignment. Except I wouldn't want it to be a wooden camera. If sky is the limit on price there are much, much better materials than wood.