It really depends on how you plan to use the car, and how often you will drive it.
I had a 981 CS for ~2 years, which probably splits the difference between an M2 and 4C in terms of "rawness" - the 981 was my DD and I loved it...but it also didn't provide very much utility or practicality. Or comfort on longer, less-spirited drives.
If you have a 3rd garage bay, and want to drive it a few times a week and always for fun, then I think a very raw car is absolutely justifiable. If you are going to be sitting in traffic in your DD, things like power steering (non-existent in the 4C) are going to be missed.
Both are good choices - just depends on which one fits you and your situation best.
