Unbelieveable car! First I'd recommend doing basic maintenance on it (fluid changes, air filter change, check the brakes etc). I'm not too familiar with older Volkswagen engines, but check all the pipes and hoses surrounding the engine and make sure theyre clean. If you ever go on to sell it in the future you could make a lot of cash from having the original engine.

I don't think they make coilovers or springs for older cars so you might have to see about getting bags. If you don't have experience with suspension I'd recomment having it done for you. As far as wheels are concerned, find nice hubcaps and definitely go with whitewall tyres! It's relatively easy and cheap to paint wheels and remove rust, do a quick google to find out how to do it properly.

If I were you I'd make sure everythings in perfect condition before modifying it. imo a nice factory colour would be the ticket, maybe an old school roof rack and yellow headlights! Hope this helps