I tune the non batter side of my snare drum quite high, checking that the lugs are nice and tight. My batter side is NOT tuned too tighly but enough so that the combination gives me a decent sized crack sound where I can hear the natural sound of the maple drum coming out.
For rack and floor toms the non batter side (clear g2s or g1's) are simply left loose to nearly slackened off completely. I have played around with tightening them right up and half way, but when the non batter side is left loose, produces a longer 'boom' sound after hitting the batter side, which i like.
My bass drum non batter side is tightened so that the skin has no visible lagging, but my no means is overtightened.
I check all skins on my kit about every two or three times i play, when you get into a habit of checking and resetting non batter and batter side skins it can be done pretty quickly - 10mins max, and makes a big difference in the sound of your kit.
on my toms and kick I tune the resos the same pitch as the batters- I get the best, least dissonant natural warm organic sound out of my drums. On my snare it depends, but usually the same pitch or a little bit higher.