I've had my '04 X50 for about 2.5 years now and have only done a few appearance mods. It has an mashaw GT2 front bumper with carbon lip, 19" HRE P43R wheels in chrome, and the standard cleared side markers. Factory options include the X50 of course, plus sport seats, short shifter, and a sport steering wheel. I'm a 10+ year Porsche 996 guy, and also a pretty serious car modder.

The car is driven about 10,000 miles a year on the streets and will see a good amount of track duty. I still have the OEM 18" GT3-style wheels so those will get dedicated track rubber. I have a couple of areas I want to upgrade:
1. Suspension/handling
2. Power

For the suspension, I'm looking at a couple of things. One concern I have is dropping the car too low since I already have trouble with the front carbon lip, so I want to stick with 1" of drop.
1a. X73 suspension
OR
1b. Springs & Bilstein HD struts combo. - What springs would you recommend for not too big a drop but an upgrade in performance?
2. Sways & endlinks - Looking at H&R plus Agency Power endlinks
3. Better alignment - What specs should I be targeting?

For power, I'm looking at:
1. EPL high altitude flash
2. Billet diverter valves
3. Upgraded fuel regulator
4. One step colder plugs
5. BMC filter
6. What else do I need to add to this list?

My clutch also started slipping so it's time to upgrade that at the same time. The OEM model is hardly sufficient for the power I have now, so what clutch should I be looking at that's able to handle up to maybe 550-600 whp/wtq and is good to drive a lot and doesn't have a super heavy pedal feel? I figured on sticking with the stock flywheel.

While money isn't a huge concern, I have 3 cars in variously serious states of modding so I am trying to do this relatively economically.

Any thoughts on where you'd go if you were me given my use of the car as both a street and track machine that gets driven a good amount? And answers to the questions above?