Road bikes are pretty high priced if you don't know how much you're going to use it or like it. Plus, I think a fresh, new top of the line mtb frame would be put to better use by you than a new road bike.
I have had a road/CX bike for years and do random rides and training, but I use my XC bike way more.
I have had a road/CX bike for years and do random rides and training, but I use my XC bike way more.