I have relatively tight opening ranges for six max
*ATB is any two broadway
AJ+, KQ+, 66+, ATBs, A2s+
AT+, KJ+, 55+, A2s+, K9s+, Q9s+, J9s+, T9s+
A9+, ATB+, 33+, A2s+, K7s+, Q8s+, J8s+, 97s+, 65s+
A4+, K9+, Q9+, J9+, T9+, 22+, A2s+, K2s+, Q5s+, J7s+, T7s+, 75s+, 54s+
I was thinking if you trim the fat off some of the range from each position, then it's essentially a 3 bet range. If MP raises and hero is on the button, I would drop the lowest parts of each hand category and 3 bet the rest.
AJ+, KQ+, 66+, ATBs, A2s+ becomes AQ+, 77+, ATs+, KJs+, J10s+, A5s-A2s. so removed AJ, KQ, 66, A6s-A9s.
Currently using this as a guideline for 3 betting. Let me know what you think. I understand it's a linear 3 bet, which usually doesn't seem like a bad idea at low stakes where they do not 4 bet very often.