That looks very similar to my 650b gravel bike. I have a 71 degree HTA and 50mm of rake for about 65mm of trail with 47mm tires. I went with a longer front center and a 50mm stem with a bit less saddle to bar drop for a more MTB like feel on singletrack trails. I really like it, but my background is more in the MTB realm, so the flop is nothing compared to my full rigid MTB with a 68 degree HTA.