To push back a bit on the Satch Track sounding “too fat,” it’s actually pretty tight, the problem is that it’s dull.
There is one easy fix for a dull pickup - it's disconnecting the neck tone pot.
It was the cure for a Steve Morse neck Humbucker, which was super warm and dull. Upon disconnecting its tone pot, it became a totally articulate and clear Humbucker for me.
Try it for the Satch Track and it will totally transform it.
If you're set on trying other Pickups, the Fast track 1 is definitely great, nicely bright and sounds like a cross between a humbucker and Singlecoil. I love it in the neck and it balances great with hotter Humbuckers. I ran mine with a Breed Neck model (which I use in the bridge) or with a SuperD.
The Cruiser Bridge is another great option for the neck for brightness but if you play a lot of cleans, there is definitely a big volume spike when switching from the Cruiser Bridge in the neck spot to a hotter bridge Humbucker.
I wish the Cruiser Bridge was louder, it would be one of the best Single Coil replacement pickups in the neck spot IMO.
It balances fine with a Humbucker up to PAF Pro hotness, but nothing hotter than that IME.