All things being equal, (I hate using that term) are bents stronger than hip and valley timberframing? If the "All things" are the same builder, with the same timbers, and the same good judgement on joinery, and average runs and spans for each style, in the same climate, etc.

I mean strenth, strength.

tapered timbers? sure I guess. Never used them but sounds cool. It would be quite a trick connecting jacks to tapered hips. different clips and such. lots of work. but if helps to answer the question..

a dome is an arch rotated in a circle, which of the 2 is "stronger". A hip or valley roof is a common gable rotated in a circle or some part of. I dunno but that's my best guess if I understand the question.