Check out the Rodeo Labs Flaanimal 4.0. I have a 3.0 I got when they were blowing them out and it's been great. I built it up with Sram 1x and run it with 700c 32mm tires on the road and hardpack 650b x 47 for gravel and dirt. The 4.0 is definitely not the cheapest frame around at $1500 but it's 725 steel, comes with a really nice carbon fork, has a billion mounts, and is super flexible with drive train options.