The FPGA is not loading anything from flash. Even with a heat sink it gets to 74 degrees.Hi,
we know very little about your application.
So generally speaking: Reduce the current drawn by the FPGA.
High current my come from
* high clock speed
* heavy processing (many switching nodes)
* short circuited outputs
* outputs fighting against each other
* floating inputs
and so on....
so maybe do a supply current test with no code or with all I/Os programmed as weak pullup or pulldown, just to get a clue about expectable idle current.