Andrew - definitely interesting, especially since you arrived there via careful and nuanced consideration of numerous saddles. Makes me feel even better about my decision.
Hardtail is a Chameleon (73 sta) and trail bike is an OG Hightower (74 sta). Saddle is kinda close to center on Chameleon and pushed pretty far forward on Hightower. I'm mostly arms and legs. Running a 185 Revive on the Hightower with a 490mm seat tube and 20-30mm to spare.
Run the bars on the lower side for a trail bike. Ride the Hightower on rolling terrain with lots of mellow grades and may be on it for a few more years because I don't want to give up the geo. If I had to replace it right now, would almost certainly be a Revel Rascal.
Obviously, the Titan will have pretty "modern" geo. Anticipate having the saddle in the middle or even pushed back slightly.
I thought the marketing on the 60x was confusing so I called SQ Labs USA. They talked about it more as a "gravity" saddle than an ebike saddle. I like it on a wench-and-plummet bike where I run the bars a little higher and spend most of the saddle-up time with the front wheel a decent ways above the rear. Conversely, it's a lot of saddle when you're in a little more traditional/aggressive position. 611 feels much better to me in those scenarios.
I would discount the ebike label on the 60X. I just got a new 611 and it had an "ebike" sticker on it. Forget exactly what the sticker said.
I'm guessing the prominence of ebikes in the marketing of the saddles is related to their being based in Europe and ebikes being so prevalent over there - sort of like what we've had to suffer through over here with "enduro." I'd think of the 60x as a gravity or wench-and-plummet saddle that might be especially appealing to larger people.
Finally, a tip that might be worth sharing. With a slack STA and a bike yoke post, getting the nose a little below horizontal (sqlab recommendation and my preference) meant that the end of the front saddle clamp bolt was close enough to the saddle that when the saddle flexed a lot it barely hit the bolt. Was starting to nick away at the saddle shell until I caught it. Just cut 5mm off the end of the bolt and was good to go. Have no idea if this would have been an issue with other saddles. Also possible this would not have been an issue with their v2 saddle clamp. Still, good thing to check for those of us partial to slacker sta frames and $170 msrp saddles.
BTW, thanks so, so much for this site. It is a complete breath of fresh air and helps me stay in touch with the ethos I want my riding to embody.