It depends on who is 4 betting you. The first question you should ask yourself when you 3 bet with any hand is who is going to 4 bet me. If you are never getting 4 bet then yeah blast away with marginal hands 3 betting. Hopefully you will be in position if you get a caller. If you are getting 4 bet a lot then 3 betting these hands could be trouble. Calling a 4 bet is going to tricky to play post flop because now the pot is getting bloated. You will be playing a big pot with not so strong cards, possibly out of position. This is great for the 4 better, not so much for you. Good luck!
unless there is a distance against the player, then I think it’s not worth expanding the range, but playing more tightly, if the player is playing loose then it’s too early, as for me with such hands it’s not worth aggravating the situation
You have to decide how your opponent plays. If you 3bet a tight player with those hands perhaps understanding what he would raise initially with is importatnt. Those plays start with a tight range and will 4bet or call. They are usually not going to fold.
LAGs on the other hand may call or 4bet you. Do you want to be stuck with a marginal hand aginst the LAG.
I would fold marginnal hands to a 3bet, unless you are very confident playing flops with uncompetitve starting hand.