+1 for not rulling out alu.
As for HA, 69 is pretty slack, while I appreciate it’s personal preferance I think you could think about it more holisticly, especialy as you mentioned shorts CS’s. I think wheelbase probably has more bearing on bike handling than the other measurements, especialy as slack HA is generaly coupled with a short stem to make it feel similarl to steep and a long stem (then a longer TT to keep reach consistent, and push the wheelbase out further giving even more sability).
Short CS + slack HA = medium wheelbase
long CS + steep HA = similalry medium weelbase.
My El Mariachi has a 72 HA and quite long stays, and I’d say I use it for more ‘trail’ than ‘XC’. I’d never have asked for it to be slacker/shorter like the 2014 version, which may be ‘better’ but I’ve not ridden it. But then I think it’s more to do with skills/balls than bikes, most XC races are probably more technical than most weekend warriors would describe as ‘trail’.