This is a chance OPS on its third year (parents unknown), pros it is winter hardy (zones 6 -5) has survived 3 years without any protection - (brought it indoors this year), it is very fragrant and repeats with a myrrh fragrance, it is also fertile and sets hips, cons the stems can not support the weight of the blooms, do you think this might improve as it ages? Or any suggestion for crosses?
It’s certainly a pretty thing. If it’s healthy and hardy where you are, and you have enough room and energy, I would keep it. What else do you have with equal hardiness and health? That is the direction I would head first. It may result in the stronger stems you desire. Those would seem the less important compared to the health and hardiness issues.