9.5 is too wide on a MK4 front end that's not modified past simple fender rolling. To really work 9.5"s I think you need pulled fenders, at a minimum. Not everyone will agree with me thanks to the plethora of crappy rota's floating around this forum...
So, I would get 1" smaller barrels for the front, bringing the wheel to 17x8.5 et42. Now you've got a workable wheel.
I'd get 215/40 for the front, 225/40 for the rears, I like a little bit of poke, so I would get custom 27mm adapters for the rear, and 18mm for the front.
Now for your answers to the way you probably want it.
Now, if you like 17x9.5 wide wheels on your front end, you're going to need to get low on the offset, something like 15. I know you need about 18/19 to clear a 9, so 15 or so should do it on the 9.5"... so you're gonna want 40mm adapters... You might have to go bigger than that.. If you want to run the 9.5" wide, you'll probably want a 205/40/17 tire on there, but then you'll still have wheel gap because you won't be able to lower the car enough to compensate for that tiny (on a MK4) tire.
Lips and barrels will be difficult with the RS178s, they are 17" but use a 16" face and the lips and barrels upconvert them to 17" so a 17" lip or barrel will not work. You will need custom lips and barrels.