Hi Dale, its all down to what your preference is matey, here is mine lowered 30mm on Apex springs with 16" wheels. I've never been told it looks odd? with 16's in fact quite the opposite, also them not filling the arch i dont understand either as i cant even get my foot in between the wheel and the arch so i guess they fill it quite well.
I used to run 18 inch wheels with 35 profile tyres and it was an absolute nightmare on our roads in Britain so i went down the 16" route, got a cheap set 1st to test and then found a set i liked.
Like i say the other guys aren't wrong its just preference, what car modding is all about.