Your/my standover is lower, toptube for CX is lower to aid in dismounting/clearance so you don't crush thy nuts on the toptube.
CX bikes should feel a tad smaller for the climbing/spinning/dismounting
done while actually riding them in CX conditions. I think the toptube length
should be more important, CX setups are a bit different than road cuz of the geometry required in the sport... my seattube is much shorter, standover is lower... overall saddle height a touch lower than road but reach & setback are the same... this is for me though, I don't know what's correct, but it feels good to me...