I was suggesting that you try and add the fx10 to your existing setup. That way you could just run it on the treble side more after your OD you have now. That way it treats the OD and brings out more high end sparkle. not that you use it strictly as an OD. I'm not that would work anyway because the fx10 is so clean. Hopefully you'll find what you're looking for either way. It's not easy, finding the right tools for the job. I totally understand what you mean about not wanting to get too "metal" sounding. Yet you need an OD that's not going to mush up on you like a Blueberry would or the like. If you know how to solder at all, I can't recommend the Pork Loin enough. Modded though. All you do is swap one capacitor out and you're on your way. It removes the sorta blanket from the PL. It opens up the high end and you still get that lovely, more organic type drive with the high end sheen at the same time.
The rusty box will def give you that punch you're looking for and if you use it as a dirt pedal alone, you get all that other tone shaping then too. I used to have a GK rails pedal as well. This could also work for you quite well. Def packs some serious punch. Hopefully you'll be able to find one. As far as Rats go, it's def in the trebly side. But with a Rat like the Blower Box or Rat/Cat tail, these Rat variants are great on bass. They were designed that way. And they will also do great jobs at getting a drive tone. However, they could be a little too aggressive sounding like you said, even at lower gain settings.
But I honestly think the OCD circuit is the one you're after. I hear the new v2 that just got released supposedly took care of the low end loss of the previous ver. And the Dunwich and Bedlam are both wonderful with low end retention as well as being barley there drives with some serious sparkle. Great with tube heads.