The 360 degree detection only works within 10 meters. Beyond that he can only sense electrical systems, so he wouldn't be able to sense your character's mist form unless he was within 10 meters, for instance. It works by saturating the environment in his vicinity with a very low-level electrical field, tuned to his specific variation of bio-electricity. It has no effect on the environment, but when an object passes through it he can detect that disturbance. He was also unable to sense LeeRoy's character, due to him being an undead zombie animated by black magic instead of the normal electrical impulses of the nervous system. This ability has a logical progression to it, and thus weaknesses can be deduced and utilized. Is it easy? No. Can every character do it? Not necessarily. But it makes a certain amount of sense and is congruent with the way the rest of his abilities work. Whether it was overpowered or not was up to you, and you deemed it not. Everything it can do was clearly outlined in the CS, and accepted. The same is not even remotely true of your shadow vision or mist form ability and the ways you've attempted to utilize them. There is no comparison here.

As for all the other things you mention, those too, were very clearly outlined in the CS, and accepted. I have not attempted to use my character's abilities in any way that was not congruent with the information given in his CS, which again, you accepted. If you want to send all the CS's back to the drawing board, that's up to you, but until then I would really appreciate it if everyone would just stick to the things that are in their approved character sheets. This is why detail is the fundamental tenant of a good character sheet for a combat RP. It prevents people from ending up in arguments like this one when someone uses an ability in a way that they think is fine but was never approved because it wasn't in the CS.