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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Hot: 2001 Estoril M Roadster
ZCP 19's michelin supersports, ZHP knob, JL 8W3
Cold: 2002 TiAg M3 6mt ZCP 19's michelin supersports, deoranged, dechromed, led tails, ZHP knob, UUC SS v3, GROM, OEM 18's w310's,
Fun: 2006 YZF-R6, black