Yeap, I think frame is really good quality (geo and carbon layup) - I‘d say probably a bit lower than e.g Merida - so solid, well built for the price, above VB etc and on par with Yoleo and Winspace. So pretty good deal for what it is. But not exceptional - tb clear and transparent.
I liked the stack, as it enables me to run most probably fully slammed. (My 2x brocken back doesn’t allow something more extrem, but this ones fine).
Though probably just as my personal recommendation and experience. You can play around with stack (spacers) and reach (saddle position and stem length) - but the Overall geo (angles, saddle position, toe overlap, chainstay length) - but the ‚corrected‘ position should match what you need. Just do the simple maths and calculate ‚corrected‘ Stack & reach etc.
Regarding ER9, Sensah, LTwoo…even as interesting as it looks. I don‘t wanna be the Beta version tester. You can get SRAM parts at good discounts (and buy Sunshine cassettes etc on AliEx).
Rival AXS levers is the same like Red (just not the titanium screws = 10-20g). Save the money for a Force front derailleur and of you can get a used Red rear derailleur, even better.
KMC chains are awesome…and Ingrid Fake/copy from Zeroing at AliEx is 60 bucks for the same weight (at least close…and lower than Ultegra etc)…but just my 5 cents building that stuff