The fact that Minerva is a crutch on Pirate Life G should inherently make that map harder than the rest, because of how RNG assassination is.
Hell, I was using Berna and Saki and still suffered during the gilmen rush.
At least the other maps are more straightforward in how you should handle it. Solano was all about DPS. Horace had tricky placement and heavy micromanagement with hard-hitters and lichs.
Rika... had that really stupid trollworthy Efreet, so that was why it took second place for me. I looked up a video of that, saw how idiotic its pathfinding was, and decided to nuke it with Nanaly/Karma early just to get it out of the way.
Azami and Ada's G maps were more like X maps, so they aren't really worth mentioning.