dspic33f power consumption
First of all, you can get 60 MIPS with less than 60 mA if you don't use dsPIC but an ARM7.
Second, Idd is what the microcontroller maximum uses, that does include but is not limited to the core. All peripherals such as timers, serial interfaces and so on also consume power and that power is (usually) included in Iddmax.
On top of Idd, you can drive external loads by sinking / sourcing current through port pins. Adding up all absolute values of those sink and source currents must not exceed the 200mA, otherwise the device will such an early end of live.
For you heat sink, it is actually important to look at both BUT measure your current and you will probably see less than the max Idd all together unless you drive several LEDs directly with the port pins.
All in all the dsPIC seams to be a device that uses way too much power for what the performance is.
Think about ARM.
Bob