From monday to Thursday I don't have much time to spend playing SH3, so I like to play it almost the same as you, with SpySat and all those goodies at 31% realism, but during the weekend, I am more relaxed and have more time, I pull it up to 50-60%. I have to admit that my skills are still poor to play at higher levels of realism.
I know that I enjoy both realism and fun, but I tend to like more the fun part of it, rather that the realism and historical side. That's one of the excellent things about SH3, you can set it the way you enjoy it the most.
CapZap