Setting Up/Decrappifying a Schecter Omen-8

[ElectricBaliset]

So, there have been a few threads about this guitar, and people have even mentioned having gotten them to sound nice with a proper setup, but they're old af, and my questions are much more to the point of that setup work.

I have an Omen-8 that I'll probably hang to for a while. For the price point, it's actually quite a nice find, but it has two major flaws (besides those somewhat wonky, nasal pickups) with which I just can't hang:

• That Schecter-specific scale length of 26.5" is not at all a fit for F#. No big deal here; tune it up to G and the tone and performance is actually pretty redeeming (though that's not to say the bottom string has no issues of inharmonicity to speak of).

On that note, though,

• The string tension is out-of-control rijunkulous. This thing ships with Ernie Ball's standard 8-string set; the bottom 5 strings have absolutely insane tension, if String Tension Pro is to be taken as a rough guide. Three of the strings hold tension above 25 lb., skewing the average tension per string to more than 20 lb.

I aim for roughly uniform tension across the strings, or at least progressive tension from ~16.5lb. on the high end to 20 lb. on the low end as a hard maximum; most of the time I try not to exceed even ~18 lb. on the low end. The way this guitar is setup, that is pretty obviously impossible, and the action is horrendous and rife with buzz towards the first fret.

So I'm primarily looking to hear from folks who've set one of these up before and had some serious play time with it after the fact, particularly if you were looking to lower the default tension demanded by the neck while keeping the action at a sane level.

Obviously a neck adjustment is forthcoming. I've done setups on Schecters before, though, and my experience is that the neck seems really hard to get right. By the time you've got enough bow to work out the buzz, the action is insane. On tune-o-matic models, this is much less of an issue - you can just take the bridge waaaaaay down - but the Omen-8, of course, has a hardtail. Basically, for anyone who prefers roughly the same tension as, say, a typical .010-.046 set on a 25.5", how were you able to get the right balance between decent action and minimal buzz?

Moreover, was a nut replacement necessary? The slots don't seem all that low, but my experience with setups recently has been that low-cut slots are shockingly often to blame for buzzing near the first fret (or worse yet, if it's really bad, on the open string).