Which types of speakers are ideal against a wall?

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.

Nice description!