Suspension v wheels/tires v coils?

Hello all,
I did my first HPDE event last weekend and I am hooked. I am going to preface this post with the obvious, I will continue to get seat time and improve my driving skills. I want to set up the car to be as sound as possible on the track. I will still drive this car on the street, The car is currently stock PP GT, with eibach sport line lowering springs. I am considering what to buy next...

1. I am considering getting a squared wheel set up, I would like to possibly get into a light 10'' wheel with some ps4s 285/35/19 tires.

2. I am considering these BMR suspension products

CB005 Cradle Bushing Lockout Kit, level 2
CJR002 Mustang Chassis jacking rail, super low profile
BK055 Bearing kit, lower control arm, rear, premium
TCA048 Vertical Links, Rear Lower Control Arms, Polyurethane Bushings
TR005Toe rods, rear, On-Car adjustable, rod ends
SB043 Sway bar kit with Bushings, front (SB044), rear (SB045)
ELK012 End link kit for sway bars,
CB006 Chassis Brace, Front Subframe, 4-point
BK051Differential bushing lockout kit, polyurethane

3. Coilovers/upgraded shock/struts with CC plates and strut mounts
Open to suggestions in this area as I am not sure

I am trying to complete best bang for my buck performance upgrades to improve handling stability, and the cars total ability on a road course. any input is highly appreciated, if that means a mix and matching of ant of the 3 categories I would appreciate the input. Thanks.

IMO, ditch the sportlines. They're too low, and mess up the car's geometry too much.

In order of importance, since this is HPDE, handling and confidence in the car comes first. More grip after that.

As such, I would go with the following:
BMR SP083 handling springs
Koni yellow shocks and struts or Bilstein HD or Steeda Pro Action adjustable
CB005 cradle lockout kit
Camber plates of your choice
BK055 bearing kit
TR005 toe link + and take the bearings out of your stock toe links and put them in the knuckle
Front upper control arms with bearings (Optimum performance already sells them with the J&M Bearings, Steeda soon to follow).

Wheels and tires after that. Apex Racing wheels are light and affordable, and you can get 18" that fit the brembos, which opens up a lot of track tire choices. They also have 19".

I found an upgrade to double adjustable struts/shocks - mine are KWv3 - makes a huge difference in handling compliance and grip. This is a kit with springs included. The addition of MPSS tires on stock wheels made a large improvement too. All the other stuff may or may not improve grip. But of the four track events I've done with the stock suspension and with the upgrades mentioned, confidence was greatly improved because the car is predictable and is progressive through the full traction circle. I don't have axle tramp or any of the suspension issues commonly discussed when drag racing the car.

FWIW, I read where a vendor built an STR car (Miata) and tested light-weight wheels against the typical cheaper and heavier competition. The end result was no improvement in times despite how the car felt to the driver. I read anecdotal evidence suggesting the same thing.

We aren't talking about WtW competition where fuel, tire and brake management are king. Rather it's A/X and HPDE/PDX where fewer than 60 seconds or about 20 minute runs are the norm. Not sure spending a lot on lighter wheels will add that much if any benefit outside of looks.

The Apex wheels are relatively cheap, and I love mine. However I'd have a hard time passing up a set of SVE wheels with Black Friday sales going on.