Interesting that you hear similarities in the Old Guards and the T-types. I've got an SG with the T-types and while I love the bridge, I cannot stand the neck pickup, it sounds like it's got a blanket over it. I put an Old Guard neck in and it opened right up, but then sounded much more modern compared to the T-type bridge - more instant attack and a touch more compressed. Much better pick attack though, so overall I preferred it, but seeing as I love the bridge I'm trying to find a better match.
As for your other SG, you might have trouble finding pickups without that upper-mid push, as that tends to be a sweet spot for making single notes sing. The Riff Raffs are pretty open, but do have a bit of that snarl which means they respond well to high gain - the site description even goes out of the way to point out the focused upper mids.
Honestly I'd suggest the Stormies if you hadn't already said they weren't hot enough for you. The Black Dog has thick mids, and yes, the weight is more in the low mids, but, having A/Bed them, the upper mids are very similar to the Mules, so if you didn't like the midrange of the Mules, I'd hazard you probably wouldn't like the Black Dogs either.
The one thing BKP don't do is an Alnico 3 option, and I think an A3 PAF/T-top style pickup may be exactly what you need, given your dislike of too much midrange but wanting something that can take high gain well. The A3 pickups I've tried take to gain really well, while not pushing the focus on the midrange - now obviously the wind plays a massive part in how pickups respond, but I've played a few A3 pickups and they share a characteristic of balanced response and clarity without having any of the extremes of other magnet types - A2 tends to have a sweet top end and can get flubby, A4 tends to have a fairly distinctive crunchy attack, and A5 tends to be crisper.
You could try magswapping a BKP set or see what other options might suit, but I'm not going to go into promoting other brands on the BKP forum.
Your best bet is probably to email BKP with your requirements and see what they say, they'll be able to offer better advice on their range than any of us. They always respond quickly and their suggestions are usually spot on.