I am an advocate of alternate positions, alternate toe-ins, especially related to Imaging for one or two listeners.
I move mine frequently
Furniture Type Dual Wheel Caster's Axels are firm, single wheel axels, even high quality, wobble.
3 (not 4) Casters. will always be steady, no shims needed anywhere you move them. More downward weight (+33%) per caster.
An apron/skirt (my current speakers shown below) concealing the casters automatically prevents tipping.
Rear Anti-Tip blocks. 2 casters up front, 1 rear center caster, no apron/skirt: you need to prevent tipping.
Put 'anti-tip' blocks in the rear corners, just a little shorter in height than the casters, they only touch the floor if the speaker starts to tip.
Lastly, tilt: aim the tweeters at seated ear height (see the unfinished pine 2x4 above my front casters, lifts the front 1-1/2". The upward tilt also alters the angle of reflection off the floor and ceiling