Happy Holidays!
Sp-cycle g068 is a clone of the new canyon grail... so that would be best to start with.Tantan GR201 is another one, even lower stack - but maybe a bit too long chainstay, and geometry is not that great in larger sizes.. if S or M is your size, then it looks great geometry wise.
Hi Im'm looking for some gravel frames with a low stack, comparable geometry wise to Cube Nuroad, Canyon Grail or Cervelo Aspero 5. Preferable not a clone of these, but would be okay as well, haven't found much at Tantan.
SPCycle G069 is basically a Grail clone, but with slightly wider tyre clearance and T47 instead of BB86. Airwolf Y0FR68 is an Aspero clone but I wouldn't recommend due to quality issues with Airwolf.
I don't think that the G068/G069 is that extremely racy. 145mm headtube in small, with 480mm seat tube. It does got quite big reach - especially in the larger sizes. But that can be a little bit compensated with a zero-offset seatpost and it is supposed to have quite short stem. 70-80mm typically.Also since seat tube is 73.5 in pretty much all sizes (not extremely high) you can always adjust the saddle a bit forward with a zero offset post, and it will be more relaxed.Also you can also add a little stack with some spacers if you think it is to low.The GR201 frame does indeed have extremely low stack, so if that is a concern i would stay away from that frame.