Great post! My M2's currently being built, but I have some similar plans. I also had an M4 for a while; loved the power delivery, and the exhaust really grew on me. But it was the size that bothered me, having come from smaller M cars. I also highly anticipated the arrival of the M2, but was a bit disappointed with the engine, and lack of tuning potential.
In terms of the 6MT feel, if CAE is a bit more than you want to spend, I know Ron at AutoSolutions has worked closely with the guys at P-Tech with SSK's. I think he's developed a kit for the M3/M4, which should be applicable to the M2. While it will never make it feel like a Miata, it may help. I'll probably do this myself.
Have you looked into the Ultimate Clutch Pedal? I had it in my M4, and felt it made a nice, noticeable difference. I'll be putting this in my M2
Those are some excellent weight savings with the BBK! The cost is a bit hard to swallow for a poser like me who would rarely (if ever) track my car, and just use it as a canyon carver. But I'll still dream about it
I was hoping the CF roof would have been a factory installed option, but alas, no. The CF hood + roof would be some nice cosmetic/weight mods (mostly cosmetic), but the ~$10k cost is a bit hard to justify.
As for HS, it really shows how the color is a chameleon depending on the environment. In the Bay Area, it seems like it's a bit darker and more saturated, which I much prefer.
Congrats on the M2! Love the mods thus far!