The answer is no. Speakers and room, room and microphones are totally dominant, compared to any preamp or DAC. Power amps can have an effect at high power, but you seem to have a good beefy amp. So DACs and preamps, will have an insignificant effect even if they can be shown to be marginally better.
If you have an itch to spend money, speakers are the place to put it.
Maggies are far from the worst speakers and actually quite good, but there are better speakers around, that is for sure.
I am familiar with them as they are built in the metro here. To me they are sound bass deficient and under stress when pushed.
So, they would not be my go to speaker.