Upsize to 225 F / 255 R.
I am very impressed with the Conti Extreme Contact DW (summer) and Extreme Contact DWS (summer + shoulder seasons...I can't condone an all-season for real winter, that's what winter tires are for).
Can't go wrong.
As to the "floaty" feeling, well, that's actually what the car feels like, it's just completely numbed out with the run-flats, which are truly, not the way to go. M-cars don't come with run-flats...for a reason, as they're still not very good (and too heavy, and too expensive, and too fragile if you were to actully drive on it while flat).
2013 BMW X1 xDrive35i M-Sport -- Valencia Orange
2011 BMW 1M Coupe (#205/220) -- Valencia Orange
2009 BMW 135i M-Sport Coupe -- Space Grey (sold)
2007 Mazda MX-5 PRHT Supercharged -- Stormy Blue Mica