Inadvertent pressing of the shutter can be avoided if you advance the film right before the shot. Just a thought. I do that to keep the film as flat as possible. By advancing right before taking the shot, I think the film stays the flattest in my opinion. Also, have you looked into Fuji 6x9 rangefinders? They are fun to shoot. They are kind of like a Leica shooting medium format 6x9.
Most film can handle being overexposed 1-1.5 stops. I shoot at 200 for two reasons. 1) It ensures I have details in the shadows and 2) LOMO 400 has a slight color shift when overexposed and I love the look!