Which types of speakers are ideal against a wall?

I currently have rear ported floor standing speakers (Dali Euphonia MS-4) against the wall due to no other room options.  Are these speakers feasible?   I also have 2 Rel 528s along side each speaker.  I am looking at replacing the speakers.  I also have 2” acoustic treatment w 2” brackets behind the speakers.  Any speaker suggestions in the the 5-7k range (used) welcomed.  

Modwright 150 SE 
Dali MS-4
Rel 528 Qty 2

Room 15 w open wall  and 17 L 
Larson designs speakers meant to go right up against the wall. 
Vortex by Von Schweikert speakers VR22, VR33, VR35 are designed to go right up against the wall. No port, has rear facing 10 inch woofer.  
Yep, they'll be fine, but stuff the ports with a sock or something. You'll get the bass back thanks to the rear wall reinforcement.

Any floor-standing or bookshelf speaker is designed to set out in a room regardless of whether it’s sealed, or with a port on the front or back of the cabinet - that’s how they’re voiced when built. Speakers that can truly go against a wall or in the wall are voiced specifically to do that. Unfortunately, there aren’t many audiophile options in that category for that purpose.

If you have the ability to go against the wall without the speakers being seen, or particularly if you can go in-wall, then I would recommend looking at Paradigm’s Elite LCR 7’s which are designed to go in-wall. However, you can take the bezel off that goes around the cabinet that holds the magnetized grill cover on and you end up with a very plain box that can stand or lay in a cabinet or against the wall. They are, however, designed to be placed up in a wall or cabinet and not stood on the floor. These are the in-wall version of Paradigm’s Prestige 95F’s.

Please go to paradigm.com with this link after it to take you directly to the model if interested /en/in-wall-speakers/ci-elite-e7-lcr
Thanks for your time and good luck in your search.
Thanks guys for all the input.   I guess I will stick with the traditional audiophile speakers and place an absorber in the port.    I’m curious if the port foam inserts are the same effectiveness as a sock?  Can’t wait to try.  
Some speakers are designed for using against the wall. Wilson Duettes for example, though somewhat over budget. Audio Note  UK make a range intended for boundary use based on old Snell designs and very amp friendly, the afore mentioned Larsens,  the original Linn Isobariks, Saras and Kans, nearly any Naim speaker before the Ovators (I have NBLs 5.5cm from the wall behind them) and there must be others out there. Some of these need a solid wall rather than plasterboard but you don’t have to give up scale and depth with all of these. Positioning is still important to get the  best from them but that position will be near a wall.
If you don't mind vintage, get a pair of Yamaha NS-2000. 3-way acoustic suspended speaker, no ports. You will not be disappointed and you'll save some coin to boot
Thanks Yetti & Elrod.  I will explore those options. It would be interesting to see how much scale & depth I might be missing out on. 
The ports have nothing to do with it, other than contolling volume and efficiency.  The bass wavelengths are longer than your room.
I would advise moving your subs around until you get a balanced bass response with the least room resonance.  You should get good results with two subs (it can be done with one, but you will limit your listening positions).
I wouldn't say "ideal," but some upper level Cantons suffer less than many when placed close to the wall.
The subs need to go against the back wall too.  Any idea if they would be more effective lined inside the speakers or outside the speakers?
I had the Wilson Audio Duette 2's and they had to go against the wall.  They were outstanding.  Sometimes, you can get a great deal on used but maybe still above your budget.  Raven Audio has just launched a new speaker line that you might want to investigate.  Celest Towers for under $5k.  Call James or Dave at Raven.  
Snell Type A's! Designed to be used that way! I have a pair (III's) from the original owner - bought from the Connecticut audio store where I once worked! Talk about serendipity! The Type A III's will KILL just about any of today's over-priced five-figure speakers! Peter Snell got it right!
If you don’t mind the size of the speakers, I also suggest Von Schweikert speakers VR22.  I love them but sold them since I didn’t have enough space for them.  You can place them against the wall.
If your decor dictates speaker placement, I would highly recommend digital signal processing.
While not specifically designed for against a wall, the Tannoy Legacy series is supposed to be very flexible in their placement.
You can certainly design a speaker that goes against a wall, and you can certainly market a speaker as "placement friendly", but physics is physics, and the longer wavelengths are just going to interact with the room and create resonance problems no matter where you place your speakers (actually, all frequencies do this but the problems are less apparent at higher frequencies).  Where you place the speakers, and where the resulting resonance nodes occur as a result, is the easiest way to tame those resonances.  A 100hz signal wave will be about 3.5 meters long.  Do your own math, but if moving your speakers around is not an option, then you will need to use room treatments or DSP.
A problem with placing speakers against a reflective surface is that timing and spatial cues are harder for the brain to decipher, and the amplitude of the reflected sound can be louder and more focused because of the shorter path it has to the ears.  Putting speakers in the middle of a room allows a longer interval before the reflected sound from the speaker reached your ears, and the reflected sound will be lower in amplitude.  This gives your ears a better chance to process the direct sound before the reflected sound reaches your ears and muddles things up (mostly true for higher frequencies).  Lower frequencies (under 100hz, but it depends on room size) will tend to activate the whole room and will have less directivity, but the presence of resonance nodes where waves intersect and voids from comb filtering will be more obvious.
I have 2 inch acoustic broad band treatments behind speakers with 2 inch extender brackets pushing them out further from the wall.  Is this typically a best (placement / product) practice for treatments?  I also have one in the right corner with corner brackets. The left side does not have a corner or wall.   I also have one inch treatments on the back wall but wonder if diffusers would be better here?
As mentioned the Vortex by Von Schweikert are designed for that.

The older NHT 2.5, 2.9, and 3.3 (which is a damn fine speaker) are also designed to be up against a wall.  

If you can find some 3.3's... you could do a lot worse.  Absolutely zero issues because of the wall coupling. They are designed for that.

There is someone out there that makes foam strips also for the fronts.
Most of the Linn and Naim speakers are specifically designed to be used against a wall. The Larsen’s and Gurus as well. Also several of the Klipsch Heritage series, Cornwall, La Scalla.
Vivid as not too bad very close to a wall. This was feedback from Vivid founder and also a local Vivid dealer. I have heard them away from the wall and they sounded great.