Just tried my CD32 with the hack and it is warm to the finger but if I press my finger down had on it then yeah it is hotter, so it like yours but again I have had this mod for ages on this Cd32 and it has been ok,I suppose because it has the delay line now built into it it will run hotter, but I will put a small heatsink on it like you
I just pulled the Spec sheets for the CXA2075 and the working temp range is -25c to +75c so it`s fine
ATB