I’ve got an original 29er and the bb is plenty high enough with a 100mm fork, wouldn’t fancy a bigger one.
I had trouble fitting a fat 2.25″ (or thereabouts) tyre and a front mech, this was easily solved by dishing the rear wheel over a few mm, there was plenty or room on the non-drive side for the tyre nobbles. Didn’t notice any effect, not even having to lean a bit when riding hands-free. (Now gone oneby.)
Frame still forms a great basis for an XC bike in my view, with the versatility to go more cx or touring mode (though I haven’t really explored that.)
ETA my front mech was a top or bottom pull one and I had to hacksaw off the arm for bottom pull to provide tyre clearance.