That being said, several years ago, now, as I was in the process of doing months worth of critical listening for an amp upgrade, I spent about 2 hours of serious seat-time with a Luxman integrated (can't remember the model number but think it might have been the L-550AxII) and and a pair of Focal Aria 936. Source was Rega P3 with Ortofon Blue, MoFi high-quality re-pressings and Rega Apollo. I liked those Focal a lot. I've also spent serious seat-time, more recently, with the Aria 926. Those were very nice, too, but the 936 were noticeably nicer sounding, to me.
With your amp, my recommendation would be to stick with speakers that are either 8 or 6 ohm nominal designs. Don't worry about port location(s) and all that jazz. Let your ears decide what sounds best to you. Since you seem to like the Martin Logan sound, have you heard the ML Motion 60XTi? A word of caution with regard to AMT tweeters, though. Many reviewers have advised these sound best when the sweet spot or listening position isn't right up against a wall (i.e. has plenty of space behind it). Based upon recent personal experience, I agree.
Good Luck! May the music gods be with you!