I always like to throw a wrench into the gears of peoples planning. If your usage for the bike is casual or longer distance riding on gravel and less time will be spent on pavement, and flat bars may be a reality, take a look at 29er hardtails.
Reasons.
1. There are 3 to 4 carbon hardtail frames available through Aliexpress that weight less than 1000grams and have proven to be very durable.*
2. Instead of being forced into a gravel frame geometry where the selection for short travel forks with 40 to 50mm of travel makes you have to pay a premium for a fork that really doesn't provide much travel/impact relief, you can spend less money on a better Fox or Rockshox 100mm or 120mm travel fork that weighs the same and is much more tunable.
3 You can pick up a 29er carbon fork for around $100 and you can quickly swap out the suspension for the carbon fork, if you start riding more on pavement than trails.
4 Most hardtails will fit larger tires than most gravel bikes. You can always run narrower tires.
5. Since hardtails have a slacker head tube angle, they are more stable and comfortable to ride.
Negatives:
- The frame bottom bracket height sits higher than a typical gravel frame. Therefore your CG is a bit higher
- Most hardtails use Boots 148 rear hubs. If you have other gravel bikes, they probably use 142 rear hubs, so your other wheels can't be we swapped onto this bike.
- The crank Q factor is wider than on most gravel bikes.
- Most hardtails are 1X versus gravel bikes being 2X. Many like the simplicity of only having to shift a rear derailleur. (A 1 X 12 drive saves the weight of a front derailleur.)
Edit: * Example
https://www.aliexpress.us/item/3256802796251755.html