It's cool that we have similar purposes for our wheels! I had considered a bus option, and for that a lighter wheel would've definitely been the move. For the train, it's pretty ok hopping on at my station, and I'm going the opposite way of most people anyway. Given that, I still want weight to be manageable, but I'm OK up to 80 and definitely 60.
I wasn't planning on sharing this, but I created a little fake EUC training weight set and used it to dial in what I'm willing to lug up my spiral stairs:
I like to be prepared for what I'm getting into, though this is probably still pretty inaccurate, given the distribution of weight of an EUC. Regardless, I found 70 lbs heavy, but doable, 90 liftable and walkable, but stairs were too much. So I'm guessing that most things below 80 will be ok, unless they are particularly tall.
Please don't make fun of me for this.