For what it's worth, I've been mixing in more of my medium strength hands in position when I 3-bet against opponents who play such that I don't think a flat is just plain better. When you're in position then it's really easy to pot control and get maxium value from hands like TT/AQ/KJs.

Out of position is a different story and hence my 3-bet range is more polarized.

Also suited connectors and suited Aces play VERY WELL in a 3-bet pots 100ish deep, even out of position. Putting them in the same range as AK/QQ++ gives them a bunch of fold equity and the pot is so big that it becomes correct to just felt any draw. Finally, when you do gin the flop, your hand is very well hidden.