concrete doesn't build up moisture, it wicks moisture away from tires. (your tires will flat spot and dry out on concrete) put styrofoam under the tires. I've started storing my car on the summer wheels, few extra PSI and blankets under the wheels = no problems
In gear doesn't matter, ebrake down.
Everything else you're right on the money.
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2002 TiAg M3 6mt
deoranged, dechromed, led tails, ZHP knob, UUC SS v3, GROM, OEM 220M 19's, Michelin Supersports
2006 YZF-R6, bunch of go-fast stuff