Six microphones is easy with a 5 piece kit, put one on both the most used rack tom and the floor tom. This takes the guess work out of it. The package is 1 kick-out, 1 snare-top, 1 rack tom, 1 floor tom, 2 overheads.
Seven microphones is where I changed the tuning on the overheads to be mainly the cymbal wash instead of a stereo image. I also now have a mic on every tom. I think this is the ideal for a 5-piece kit. I think that unless there is a problem with hearing your cymbals in a space this size you are fine (and if there is a problem you might have too much volume other places). The package is 1 kick-out, 1 snare-top, 2 rack toms, 1 floor tom, 2 overheads.
Eight microphones is where we start to add things for the sonic addition, not because we have to. Again we have a choice here. I think the choice is between the hi-hat and the ride. First I added it to the hat. Then I added it to the ride. You decide.