First, let's understand what a stand is supposed to achieve. Basically you want a stand that acts like a floor, so rigidity is the key. There are two schools though, one which believes in mass-based rigidity and the other in using coupling efficiencies (meaning lightweight stands, mostly based on tube or rod stock instead of hollow pipes).
The former kind of stand is common. You basically weld together two blocks of iron into a base plates, another two into a platform, and join them with a length of hollow pipe, which can be filled with sand or lead shot to absorb any movement on either plate. Then you use springs (spikes work the same way mechanically) to couple the speaker to the stand, and the stand to the floor. This is the basis for most designs of speaker stands, and the materials evolve though the fundamentals don't. Basically, this kind of stand absorbs all the vibration transmitted to it by the speaker (which is not all the energy of the cabinet walls, only the part that is coupled to the stand). Spikes ensure as much as energy is transferred as possible, and usually work better than Blu-tack or other methods.
The second kind are much more difficult to design, and AFAIK don't exist for most home situations. But since the AE5 are technically midfield speakers, they may work better with this kind of stand. Principally, the stand absorbs little to no vibrational energy, and transmits all of it to the underlying floor. The coupling of the speaker is basically not with the stand at all (at a mechanical/technical level, as the speaker is to be kept on the stand) but with the floor. The stand basically acts as a coupling rod. I am in the process of designing these stands for my own Dynaudios, using three lengths of threaded steel rod, a few heavy steel plates, and some nuts. The rod ends will basically carry the speaker and touch the floor at either end, the ends will be shaped into flattened spikes, and the base plates will ensure minimal lateral movement. The rods will be coupled to the plates using nuts. I would've posted designs but they're right now in my head only.
For now, I find professional tripod stands reasonable for use with a heavy base plate, though the amount of plastic in those stands do cause concerns at times. But for monitoring or causal use, they're fine. They cost me 3000/pr, plus a little extra for 1 inch thick glass base plates. They can carry 115 kilos each and are unconditionally stable, maids, pets and children included. They're just a couple of inches higher than I really need, which is probably their only shortcoming - in a proper studio the console would be raised above ground level anyway, whereas I live in an apartment.
Listening height - I don't really know. You have to listen to your speaker and figure out the right height. Some speakers are voiced for 5 degrees off axis balance, some for 15 degrees and some are meant to be listened to on axis. Plus users may prefer a little more exciting or a little more laid back sound. You need to set up the speakers and move your head in the vertical plane to find out the right listening height. For a wide-dispersion speaker like the Dynes, anywhere between 600 and 900 mm (height from floor) seems to work OK for me, they're currently set up at 850mm.
