Which magnepan

I have a pair of 1.7s bought new in Nov. 2013--nearly 5 years ago. I power them with a Perreaux PMF 1150B amp rated at 100wpc into 8 ohms and (I presume) around 200wpc into 4 ohms, which is the typical Maggie load.
I also supplement them with a pair of very compact Mirage MM8 subs, which are 9" cubes. The drivers are an 8" active sub and two 8" passive radiators. They're powered by switching amps making around 340 watts per sub, with peak power around 1300 w.

The room is a little more than 12'w x 16'd, with a 15'h peaked cathedral ceiling. The living room is also open architecture, with only a 4'h boundary between the living room and the rest of the floor, which features an open architecture entry hall, dining room, and kitchen. So that's a lot of space to fill, but on the other hand the spaciousness makes for trouble-free acoustics.

So anyway, the 1.7s have no trouble filling the space and do everything I've ever wanted speakers to do. The realism is stunning. Voices, brass, acoustic instruments, and especially piano has me turning my head in reaction to find the piano or tuba because they sound so real.
Of course the little subs help fill the space. I have good bass extension down to 36 Hz.
Every time I listen to my Maggies they remind me how noisy conventional speakers are.

"for the short time that I had the 3.6r's in the room, the drummer sounded as if he were up by the ceiling and I had them a few feet from the back wall and about a 1 - 1.5 from the side walls.     think I was sitting 7-9 ft away ( + - )."

Even if your speakers were along the shorter (18') wall, my quick computations tell me your speakers are about 13 feet apart, and you're only sitting 7-9 ft away. I have a difficult time thinking your imaging, soundstage, and/or focus could be very good whether you have 3 series or 1 series Maggies.
Although I have only owned 1 series Maggies (five different models), I think I can safely assume, "A Maggie is a Maggie".  The 1.7i models will have a simular sound as the 3.6 model you didn't enjoy.  You might want to re-think you room layout and acoustics before plunking down your hard earned cash.
Just my 2 cents worth. 🎻

I've had 3 pairs of various Maggies in my system since the early '80s.  They have many strengths, and one of the best among them is their imaging.  If you're having difficulty getting Maggies to image well, there are a few things that may be the issue, but the speakers themselves are not it.  I'm currently running 1.7s in my system, and I would suggest that you wouldn't want any smaller model considering the dimensions of your room.

Most potential issues have been addressed by others here, but I'll reiterate them to give them the attention that they deserve.  First, placement is absolutely critical for these speakers.  Literally inches can make a substantial difference in their performance.  Toe-in is something that especially needs to be experimented with.  Also be sure to play with the tweeters being on the inside vs. the outside edge by swapping your left & right speakers.  It can literally take weeks to fine tune the placement of Maggies until they're just right.  And, of course, you will only have one relatively narrow sweet spot.  My wife has always joked that I'm anti-social due to the single chair in my listening room...

Second, Maggies are very sensitive to what is upstream from them.  In fact, considering their relatively low price, they are amazingly so.  You really can't skimp on decent components and expect your Maggies to still sound good.  That includes things like cabling, vibration control, etc.  This doesn't mean that you have to spend a fortune, but you have to select other aspects of your system with an eye on synergy.  For example, I'm running a Rogue Sphinx integrated amp with my speakers. A very cheap amp price-wise, but the Maggies love it.  Surprisingly, I tried Rogue's much more expensive Pharaoh amp with them (that has very similar technology) and I found the sound lacking.  Again, synergy is what it's all about.  That and lots of current!  :^)  

Finally, you may have issues with your room acoustics.  These can be challenging, but can be reduced with room diffusers and absorbers. Of course you can purchase those that are specifically designed for audio, or you can just use many common items such as carpeting, shelves filled with books, draperies, tapestries, etc.  Hope this helps!  Michael

I concur with those who suggest the 1.7 -- and also with those who have suggested that there's something weird going on here, perhaps with the setup. They can sound great in a smaller room than yours and I've never heard of the curious symptom you describe.

8' ceiling should be fine and so should a room that size. Generally, you want to keep them as far from the front wall (the one behind the speakers) as practical -- 3' is the bare minimum, 5' or 6' is good, even more is better than that. Proximity to side walls is rarely a problem, unless they're within a couple of feet and then you can get too much bass.

Usually I find the best results with an equilateral triangle but depending on the room, you may prefer narrower or wider. Experiment with tweeters in and out.

The curious elevation of the highs may have something to do with room acoustics. You might want to send some pictures to Wendell Diller, Magnepan's marketing director, or one of the acoustics gurus to see what they suggest.

Planar setup can take a long time! I moved my Maggies back 2" a few days ago, and everything went to hell, God knows why. Moved them forward again and everything was great again . . . 

@addyson815-  SO, what did you end up with(and results), assuming you made a decision and moved on it?