[Edi]

No mod can do that. The chance of random independent provinces having special defenders is fairly small and cannot be modded. There are some external programs where you give a map file as input and get a completely or partially randomized version of the same map file as output, with lots of special provinces. If you want really chaotic stuff, ask Gandalf Parker. Ballbarian is the other guy to talk to, look up his Semi-RanDom application in the Maps & Mods subforum.