Ashen, what was the donor in your conversion?
I dunno, maybe I got lucky with the old Kona, not sure. I'm 6'3" and 230lbs. and haven't had any complaints other than the time I really loaded it up with two computers, associated peripherals and a multifunction printer. That was the only time I found it really sketchy at speeds about 10-12mph or so. And I didn't have the snapdeck installed, so it might have been even less sturdy than it could've been:
Just did a 16+ mile ride yesterday through some windy mountain roads at a decent clip and found the handling just fine (granted this was with light load, only my messenger bag with tools, water, sweater, u-lock, etc.). I was really expecting much worse but overall the bike rides just fine. Sort of a tank compared to a standard bike but not bad at all. Maybe the more compact frame of the Lava Dome (with sloping downtube) makes it a little sturdier?
Steve