If Dybala is still very suitable and comfortable at AS Roma, I don't think he needs to move to another team for next season either. Especially if the choice is Chelsea, which slumped last season, so obviously it will be very difficult for Dybala to return to develop there with the young players who have been brought to Chelsea. So it would be great if Dybala wanted to continue his career with AS Roma next season by continuing to work together so he could bring AS Roma to a better position than last season.
I think Dybala should remain at AS Roma; despite being injury ravaged in his days at Juventus; Dybala has been able to find some form of rhythm in the AS Roma and he did have an excellent season in the Serie A too (by Dybala standards compared to previous seasons.)
Moving away from AS Roma would mean a new training regime, doctors etc; that could hamper his fitness a little bit. Dybala should attain consistency with AS Roma.