I'm on way back from sagittarius A* (5k from sag A and 20000 from the system i started from in civilised space, i've only got class K and non-sequence stars selected, am in map mode and have removed star names etc.. the below video on youtube is my experience for every current route plot right now, if its not 5 mins, its 10.. and fps drops to 0.7 when calculating a route.
The galaxy map did not need changing for power play except for the power play influence bits, but that should IMHO not affect people who are out exploring as they are too far away to care.
Explorers took a very bad hit with powerplay.. and the below demonstrates why.
https://www.youtube.com/watch?v=nhQm3nbxYkQ
Well, there's your problem. You've got too much stuff turned on in your map. Turn off the grid, and all those other markers. For some reason, you also seem to get much better performance if you switch to realistic view from map view.