I fully understand where you are coming from and like to do what others don't but will do so if it is the only real choice at the time.
If you go with 17's I would stick with 205/45/17, the 215/45/17 will almost always be to tall and heavier and ultimately less performance than the smaller tire but also look at actual specs as mentioned on other threads, many tires are far different than it would seem using some calculator and markings on the sidewalls.
I just looked up all the tires in 16 and most in 17 and always looking at tires anyway to get all the data from them, tests, reviews, etc.....if you want a tire that can be great on the street, handle a decent amount of rain, track and autocross, probably only one or two that will do it all with the fewest compromises but the wheel size has to be determined first to pick the best one.
I have owned quite a few sets of RPF1's and loved them but they have a small inner barrel so likely not fit over the WW BBK and if you get back into tracking you might want or need bigger brakes.
I have ran Rota in the past, street, autocross and track and no issues but I never ran them for many events and picked the stronger designs, 18x9.5 for track and 18x10.5 for autocross on a highly modded and very fast Forster XT.
I just looked at a picture of the Blitz, it is one of the stronger designs they make so probably pretty good. I did not find them in 16x8, do you have a link to them, weight, offset, etc?
There are the forged wheel options but in all honestly, simply not needed when you can buy really great wheels, a full set, for the price of one forged wheel, I am talking about the Konigs but only in 15's and some a bit more costly in 17's or 15" in another brand.
For the time being the RPF1 is the only really good 16x8 for the money, the TD will be a good wheel for less but a bit more weight though hopefully quite reasonable.
If not for hitting the road to the south for the winter in our RV I would order in a Konig Helix in 15x7 to test over my brakes, I think it will fit, then get some 195 AS tires and save nearly 8lbs per corner over the 17x7, 16.8lb wheels and Mich PS AS tires I now have, 15's ride so much better and all that saved weight makes them ride better yet.
I already have ten of those wheels in 15x9 and love them, roll formed, 13.4 lbs, look great, fit my brakes, $1240 shipped!