Lubricate the button shafts and the wireform pivot points and spring with just a touch of teflon lube. Replace the flipper switches with new ones from PBR, and if you feel they need it, replace the buttons as well. Adjust the position of the switches (you have a little wiggle room with the screw holes), and if necessary, reform the wireforms slightly so that the flippers are adequately responsive to normal finger pressure on the buttons. If you're concerned with the potential shock hazard, put a small piece of shrink tubing on the vertical part of the wireform (the part which contacts the playfield switches).
Doing all this will make the flippers work just as well as the modification you're contemplating, without changing the basic design. This type of thing is a major turn-off with me when I look to buy a machine, so it's something to consider if you're ever thinking about reselling the game.

It all depends on what your other hand is resting on, and if you're wearing shoes or not. I routinely turn off games by flipping the weighted switch inside the coin door. I just make sure I'm not touching anything with my other hand. Not that I recommend that... just sayin'. It'll do more than clean out your ears and sinuses if you ground yourself while doing it.