"There is no one pant to rule them all."
Quite true, nor one style of pant. No one is wrong for wearing zip offs. They weigh more, that's true. They're a bit more flexible than regular pants, also true. To each his/her own, really, the weight difference is pretty insignificant, IMO.
I don't like zip offs personally, but hike with folks who do. I also never wear shorts while hiking, only pants, though folks I hike with do wear shorts. It's all in what works for you.
For me: 3.5-season: Railrider Bone Flat pants with Ex Officio boxer briefs. Early spring/late fall (colder temps) I'll carry GoLite Reed pants if it's going to rain. Winter: RAB vapour rise pants with Ex Officio boxer briefs. I'll carry RAB eVent pants if it's going to rain alot or hard.
I'm also fond of the MLD tall eVent gaiters, in both summer and winter. Summer when it's rainy, winter all the time.