I must respond to the question I hear most often these days..."What kind of bike should I get for riding dirt roads?" All of the cycling media seems to be drinking the same Kool Aid when it comes to this subject.
Let me start with front derailleurs...Front derailleurs are a great thing to have on your Gravel bike...Your chain will last longer because you should be in the habit of keeping it in as straight a line as possible. It will get gritty and it will make noise because of this accumulated grime but, it will wear less and irritate you less often, especially if you don't 'cross it over' into extreme configurations. The one chain ring/ no front derailleur fashion of the day will necessitate replacing the chain more often and will come with a ridiculous set of cogs on your rear wheel. Twelve cogs with the largest being a forty-eight or fifty toother. Right away you'll need a much thinner chain and on dirt...That ain't good. A 2x10 or a 3x9 will give you a much larger range of gears operating with a much stronger chain.
My next suggestion involves the front fork. A rigid fork is lighter and cleaner looking but, hey...there are some outstanding and relatively light (when compared to MTB forks) 700c suspension forks out there. Dirt roads get hammered by cows, sheep and teenagers in Dad's new Jeep Wrangler or Polaris quad vehicle. Have you ever tried to pick your way down a road that was slightly damp when a herd of cows took a shortcut from one pasture to another? Who needs hours of vibrations and stress on your wrists, elbows and shoulders. It's something I've learned to avoid, if possible.
Drop bars look cool and provide a little extra suspension however, flat bars provide a little more control due to leverage afforded by the extra width. Brakes are another issue that folks like to argue about long after the sun sets...doesn't matter, as long as they stop you when you need them. I like mechanical disc brakes like Klampers or TRP dual piston disc brakes but actually, my 'dual sport' GF Fast City (which I use for most of my rides, dirt or paved) with rim brakes, has never failed me. They all need pads replaced periodically depending on how hard you use them and on how wet your outings are.
How about waterbottle cages? People even argue about these. I like cages, it's great to have extra water on the bike instead of a sweaty hydration pack on your back. If it's a very long ride in an arid zone you better have both.