Saw your email via other address, but for some reason, the server wouldn't let me respond.... so, I'll answer you here.
I have wheels from a new S500 on my '96 Coupe. I'll attach a pix. I did this because I wanted all four the same and I got a good buy on these new wheels. Now I can rotate my tires. I think they look better than the originals... but, wheel choice is very personal thing... what some think look good, others do not. I like the look of the AMG monoblocks, but seems like everyone around here has them. Not very unique.
Personally, I wouldn't go larger than a 17 inch diameter wheel. I've seen too many tires/wheels get broken/bent in the city because of the ultra low profile tires, etc. But, like I said, its a personal choice... so everyone else, please don't flame me. :-)
No, my Coupe does not have xexon headlights. I think you'll find the 93-95 Coupes are very similiar to each other... the 96-98's are different in many respects. My headlight bulb is a US designator 9003. They are plenty bright for me. (again, a personal choice) I find all the BMWs, Audis, etc with xexon lights to be blinding in city traffic and entirely unnecessary.
I'd rather run standard headlights and spend the extra bucks on really good driving lights to replace the normal fogs. Then you can use them on the dark roads when you need them.
Why don't you drive your car for a bit and see how you like the way it drives, etc before you change out the wheels/tires?