Cramic Since you're a relatively new rider, I'd go with a more conservative choice and a "Trail" or "XC" MTB, rather than a drop-bar gravel bike. I don't know what kind of bike-handling skills you've got, but i'm going to assume that it's pretty limited regarding off-road. A 'Hardtail' MTB with front suspension and 'flat' bars will be a lot more forgiving and easier to handle, especially on fast, bumpy descents.
"Trail" MTBs are kind of your general-purpose all-arounders, definitely the most common type you'll come across, and they come in a wide range of spec (and budget) Will do fine on the trail, but be equally OK just knocking around with the kids.
"XC" bikes are highly-focused off-road racing bikes. They are fast climbers, with quick handling as well as the ability to deal with technical terrain. IF I was doing a 125-KM off road race, I'd pick something like a
Cannondale Scalpel. However, these are the kinds of bikes that 'work better the harder you ride them' so they don't really make great 'around town' bikes. (also, they inhabit the upper ends of the spec sheet, so $$$$)