Thirupurambiyam must be given the pride of the place in S.Indian history on par with Rakshashi-Thangai or Plassey, for that had the greaest impact on course of events.
My take on the Chozha, Mutharayar subject is that they both were chieftains operating with nominal acknowledgement of Pandya/Pallava suzerainity, though Chozhas claimed a greater pedigree.
There is also the Kalabhra link to Mutharaiyar, they could have been what was left over of the Kalabhra rule of Tamil Nadu, Kalabhra and Gangas of Talakkad - do they belong the same geneology. if so it would be more interesting as Ganga Prithvipathi died fighting for the Chozha-Pallava coalition at Thirupurambiyam.
I am not a writer but a avid fan and one of my dreams would come true if a great work of fact/fiction comes out on the period from Tellaru - Thirupurambiyam. That period I believe there was considerable rashtrakuta influence in Tamil polity
It would talk of decline of both pallavas/pandyas and raise of Chozhas. One major feature is how much role the chieftains played in these events. The velirs, malaiyamans, mutharaiyars etc.,