Yeah I would advise upping the camber on the front at least.
Do you know what camber you are at, at the moment? If you can, try and get -1.5 on the front. Probably wont get much more out of the bolts.
Two completely different types of tyre to be honest. RE070's are a summer tyre with very stiff sidewall whereas the rainsports are a wet weather tyre with softer sidewalls. They're both better at different things, just depends what you want I guess.
If he is talking about the good ridge lines they can get moisture under the plastic sheath that looks like the lines failed but it actually hasn't. Mine are the same.
My rattle was really bad so did it at low and high revs, I'd recommend shortening it if you can. Yeah the sound is amazing I think, my favourite exhaust I think!