hello, wanted to introduce myself

My name is Mike and I just bought a 2 year old Rosy named Luther. I've been the owner of 2 corn snakes in the past, and I am blown away by how much more awesome Luther is! I have found my new favorite snake! So docile and chill, not like the corn tring at every second to get away from me. I did have a couple of questions though. From everything I've read I see that humidity is a bad thing, but how much is bad? I live in New Mexico so we have absoutly no humidity which helps, but even then my gauge reads about 20-30%. I have a feeling this is not detremintal to him, but I get very fanatical with husbandry and would love to know the proper temps and humidity levels. I have read so many different things online, some say no water bowl, some say a tiny unspillable water bowl slightly filled, some say a water bowl every two to three days for a couple of hours or so, some say he'll get the moisture he needs from his prey......and so on and so on. To be honest with you, right now his temps are 83-85 on the warm side, with a hot spot of about 90, 73-75 on the cool side and about 80 in the center, and like I said the humidity is always around 35%. Is this good? Oh ya another burning question, when the summer comes and we blast the a/c is there a way to insulate his 20 gallon tank? My wife likes it cold during the hot new mexico summers. Maybe a blanket wrapped around his tank? Heck I don't know. Anyone that has had to deal with this please help! Sorry for the long post...next time I'll break it up into chapters!
Thanks again and hope to met you guys soon,
Mike and Luther
btw I'll post some pics soon