First upgrade...new top w/ glass window?

[Perfectlap]

wheels are expensive but will make huge difference. As will an aerokit.
Both of those will run at least $2K each. But worth every cent in my opinion,especially if you plan to own the car for a while. Your car will look much more expensive.
in this order:
wheels (hold onto your stock wheels when you sell the car)
side skirting
GT3 front bumper


Next on the list would be a hardtop (which holds value well for resale)
and then look for 2nd hand set of clear halogens or bite the bullet on
Litronics HID lights (very little bang for the buck).

If your current soft top is still functional I would make that very last thing to replace. Just spray some Raggtopp on it and it will last forevere, and look a little darker after applying.


p.s.
A silver hood crest would look really nice on Lapis Blue.