1) It is totally unacceptable to attribute Balu's success in TFM to Raja's rise. Even if a magic called Raja had never happened in TFM, SPB would have have been as successful as he is today. Already Chitra's success has been completely attributed to IR by many here, now there is attempt to bring SPB in to that fold.
2) It is true when IR entered, it was almost end of TMS. So I would not say IR was the reason for TMS's end in TFM. But PS was still going great guns and for some reason IR never utilized her properly. As fas as I know, when Janaki was number uno in TFM, PS continued to be #1 in TeFM for a long time after IR's arrival.
SPB has been a singer of choice from KVM to GVP. Do not try to attribute his success to Raja in any way.