All Upgrades of All Towers BTD6 (Very Long)

This is all my ratings for every upgrade of every tower in BTD6. It has 6 Tiers and each tier has 3 ratings, A, B, and C. A is best, and C is worst. B is in the middle. It is a VERY long list, so don't bother looking all at once, the ones that matter most are probably the tier 5s and 4s.