I think a Crux would be a great “one bike to rule them all” with the caveat that you’ll struggle to fit tires wider than 35mm. I own an alloy Crux and a carbon Emonda and honestly, if I had to pick one I love the Crux more. I owned the Crux first and was actually a little disappointed when I went on my first decent ride on my dedicated road bike. Mine is set up 1x during cross season and 2x in the summer and is generally a fun zippy ride. If you’re not racing road you’re not going to notice the slightly higher bottom bracket. Also agree with people on looking into an actual gravel bike, but I personally hated the sluggish handling on the Diverge so I’d look outside Specialized for that.
As a counterpoint, I got dropped hard at a CX race last season by a guy on a rim brake Domane… He must have lost a bet or something. Definitely don’t recommend doing this. He must have seen his bike’s life flash before his eyes every time we hit a rooty section. The temperature was hovering around 20F at least so he didn’t have to deal with the mud.