Hello Ali
First of all, having 60 OSPF routers in a single broadcast domain will cause you problems. And if I understand correctly, you have a hub and spoke topology, so all of the remote routers are listening to broadcast traffic on this single subnet over their WAN connections. So you’re using up bandwidth unnecessarily, and you are also causing the routers to look at broadcasts that do not belong to them, so they continually discard them.
The best way to resolve this issue is not to choose another OSPF network type, but to change your topology so that each spoke belongs to a different subnet. That way, you can employ routing more efficiently and send traffic only to the spoke for which it is intended. Using either FlexVPN or DMVPN would be best.
I don’t believe that any choice of network type will resolve your flapping routes, your SFP flooding and the broadcasts being sent.
I hope this has been helpful!
Laz