I was on a bike with 495 reach and 632 top tube and 78 degree effective seat angle (Nukeproof Mega).
I'm now on a bike with 500 reach, 638 top tube and 77.5 degree effective seat angle (Kavenz). The numbers look really similar and you might think the Kavenz would have just a touch extra room but it doesn't. It's noticeably shorter for seated pedalling and climbing.
One measurement that needs to be considered is actual seat angle. The Nukeproof slackened off to just over 70 degrees actual angle while the Kavenz remains steep at 75.5 degrees. It means that with the seat post at full extension, the Nukeproof moved me back a fair way but the Kavenz doesn't.
I've found it means I have more weight on my hands and feel a bit cramped on flat trails but it climbs much better. Swings and roundabouts. I've gone from a 35mm stem to a 40mm and will soon change to 45mm which I think will be my sweet spot.
I feel like if you had the actual steep SA, but a much longer reach and a slightly higher stack that should be best of both worlds? Climbs well, but fix the comfort problems?