I don't know if the G2 tires are any better in wet than the G1. I had f1 supercars on my Z06 when I bought it now NT05's. less hp than the zl1 but it is managable to drive but flooring my car in first or second is out of the question at any speed. if you not strait you can't pin it in 3rd either. it is all albout throttle control. that being said as long as you just dive they do fine.
the problem you run into is there are no all seaon 305 tires so you either have to downsize or live with summer tires.
honestly 580hp and ran I tink the car is always going to be a handfull if you don't respect the surface.
I think temparature is harder to adjust for than the rain. I have had rear wheel drive high hp cars all my life. I am used to rain. it is the the low temp loss of dry grip that suppries me somtimes.
2013 ZL1 -sold
2013 Megacab 8" lift 38"mt's