More Twang for a Squier Custom?

The subjects may be a bit misleading, 'cause I realy like the overall sound of my Squier Custom:

http://www.armeirre.de/jotka/tdpri/squier.jpg

Except new Alpha pots (500 k log.) and the the two GFS P-90s, this guitar is stock.
The GFS's deliver a nice, smoky sound with snappy hights,
but the bass- and lower mid-frequencies sound a bit too mushy for my taste.

So my question is, how can I get a bit more Twang on the E, A and D strings?

My suggestions so far:
1. install better (stainless steel) saddles
2. bone nut instead of the plastic nut
3. "better" P-90 style pickups (SD Phat Cat, Häussel etc.)

I actually don't want to change the pickups, but I'm not sure if suggestion 1 + 2 can
give me some more Twang in the lower frequencies or if this "dull bass" phenomenon is actually caused
by the aghatis body.
I never had an agathis body before, so I don't know how the wood compares to alder or ash soundwise.

Any suggestions are welcome.