Yes or no. Does anyone do it? I have never bothered but tinkering around with my bike I did realise the rear wheel was well out of balance. Is there any point in balancing it?

Never bothered but as for is there any point that would depend on how out of balance and how fast you go. I expect it would have to be really out of balance for it to be important on push bike wheels.

the valve stem did it..

Is it April 1st again already?

So its my geekyness / inner nerd then. Just an idle thought. Interestingly one wheel I tried did not come to a halt with the valve at the bottom. Motorcycle tyres have a heavy point marked on them to fit opposite the vlave

I just move my spokey dokeys around until they sound right.

Unless you plan on going over 60mph on a regular basis I wouldn’t worry too much.