Miata CSP advice

[Mike Keyes <mkeyes@interlog.com>]

Hi! I have a 90 Miata with the following: 14 x 6 alloy wheels with 205-55
14 BFG R1's. I have Ground Control Coil-overs with 375 lb front and 250 lb
rear springs with Koni single adjustable shocks. I am wondering what my
next purchase should be:
13 inch wheels and tires with a smaller diameter
modify air intake and exhaust system
new sway bars and bushings

Can anyone provide some advice regarding which of these 3 options would be
the best choice .
Thanks.

Mike Keyes