Shafaq or not, I think Iran will find it useful to induct single-engine light-weight fighter aircraft in good numbers. It can be used to cover more area for CAPs etc and also less maintenance extensive.
I don't know but developing fighter jets is an expensive journey. Look at Indian Tejas.
en.wikipedia.org
Iran would benefit if jointly produces aircraft. Negotiating good ToT terms is vital. Only go for Su-30/35 if you get good ToT else it will become a burden for IRIAF to have a maintenance-heavy large RCS aircraft. And don't go for two platforms, pick one.
For now, in my opinion, J10-C medium-weight aircraft is the best bet for the short to medium term while Iran works in parallel to develop indigenous technologies.