So looks like you can set up your gun as a limited gun for the exception:
1) no magwell
2) no comps
3) no major pF, although you can still shoot it but it will be scored as minor
4) no thumbrest , unless you use one that replaces the slide lock
You can go nuts with everything else, even work on or swap with a custom trigger. So carry optics is really more than or at least just as competitive as limited. Low recoil, same mag capacity and a periscope for fast target acquisitions. Yes limited has the major PF going for it, but speed, specially in big stages may be a better advantage.