I read something last week on the forums that a suspension kit or something is needed when you fit 17s on a 3rd gen. It didn't register at the time but now it's hit home I'm getting concerned and I can't find where I read it.

Anyone got the heads-up for me with this?

never heard of it.
Im sure plenty of people here have got 17-18" rims on 3rd GEN and never had problems or needed to fit any kit...

I've also had it serviced and no doubt the tires were rotated incorrectly, this is probably causing the grabbing I can feel on the drivers side front wheel. It's not the brake biting or grabbing.

You may require a camber correction kit but since your suspension is stock so there should be no problem in alignment (as long as its correct to begin with).

Is there a difference with the maximum diameter / width wheels that would fit an AWD vs a FWD? I recall seeing that written somewhere - i.e. some excuse why the AWD Sports only has skinny 16" wheels...