OP: yes, even with the gravel tires it felt too stiff. Not surprising, though, since all the tubing is 2x oversized and like Mstateglfr wrote, the front end is overbuilt. There's zero fork flex, so if you do end up with a Lynskey, I'd suggest looking for another fork that has some compliance. I hear that there exists a carbon fork or two that might have a bit of compliance. The Whiskey 9, maybe?

If you go steel, I did all the readings this summer on that, and short of a custom frame with old school tubing, the Black Mountain Cycles MCD comes the closest and the price is very good. There's a world of difference between the compliance of the MCD with steel fork and the Lynskey with the Lynskey fork in my experience. The MCD is only 1x oversized (compared to an old style steel frame) which gives it nice lateral flex at the BB and fore-aft flex at the fork/head tube junction.

A 1x oversized ti frame with 1 1/8" steerer and steel fork would be optimal, IMO. The main reason to go ti over steel would be that steel dents more easily.