Speaker distance

For a sealed design, the equilateral triangle or similar usually works great. Add a port, and the room interaction multiplies. For planers, it becomes even more complicated. 
 

I am sometimes surprised as to how the rules can be broken to good effect. In college, one year I set up my double Advents about two feet from my mattress (which was on the floor). I used to listen at night in my bed, my head two feet from the plane of the speakers, which were about 8 feet apart. It was immersive and holographic, with substantial sense of depth (my Marantz 7 preamp helped give the depth, along with my Ampzilla).

The best way?  Put your speaker stands on casters.  Otherwise it's too difficult to experiment, even if your speakers are 77 lbs. each like mine.  You'll find the threaded diameter of speaker stand feet or  spikes is 8mm, so you need a threaded stem caster size of M8.  There are self-leveling casters so after you find the right position you can raise the caster wheel so the caster rests on a solid foot.  It may raise the height of the speaker an inch or two but finding the right location for the speaker is more important.  Good caster wheels will damp vibrations on a hard floor.  

@eisen0169 

Making them movable while experimenting is a great idea. Although, I would recommend furniture sliders...like from Amazon. They are cheap, easy and very temporary. You ultimately want them on spikes (with or without the dimpled coins) or even better something like Townshend Podiums. 

@curiousjim your description is so accurate, I feel like I am in the room. Move over!

Ok - it seems there are a lot of opinions.  Looks like I gotta put it together and experiment.