I couldn't get the current version of that map to work properly, if you select GR it doesn't zoom in, but it did with TS (using Firefox, didn't work at all with IE 11).
Re patrolling areas, I thought that might be the case, hence I moved to directly below Merope around the border zone, which reminds me I found something odd last night, I went to 3-4 systems which had no NHSSs (hung around at least 10 mins), yet they were 135-140 LYs from Merope. Only the last system I visited broke that empty run (as per log, HIP 14843).
Re time spent around the ctr, I know I've inadvertently added to that, when my hold is nearly full of (mostly) escape pods &/or my hull has taken significant damage, I've sometimes headed back to Merope (or near to) for repairs, or the last time was to buy a shutdown field neutraliser (which I promptly stored as it would've taken a precious utility slot!

). Other times I've headed out to 1 of the line of stations between Merope & the bubble.
Anyway, on route there & on the way out I encounter a lot of NHSSs, which I can't ignore as I'm rescuing people from the Thargoids

. I shall be going to whichever station is nearest next time, so it probably won't be in the ctr.
I would think cmdrs visiting stations is generally why their are more NHSS encounters around the ctr of the Merope bubble.
Forgot to say earlier, looking forwards to the re-written plug in
