Big draw on the turn in big pot

[Tugg]

Results are that the Button had KJ, and a mp limper had A7.An A came on the river and the mp won a huge pot.I find myself in these situations quite often where I have a big draw in a huge pot and I was wondering if this is the type of hand I need to be more aggressive in.I believe that had I bet, the button most likely would have raised and maybe? the mp would have folded.I was wondering if this is the time to try and buy a few outs with aggressive play, or am I just pissed because I lost.