OK folks, here's the disclaimer: My response is almost as sleep-inducing as the movie was for some back in 1979.
My vote is for the SLV, which stitches together every bits of filmed material - even the bit without the blue background so, oops, the scaffolding is visible but at the time it didn't matter because it was cool to see additional footage of Kirk taking the spacewalk in what was also a different looking outfit... to see that edition in proper widescreen should be sweet, even if it begs the question of when he changed space helmets.
The theatrical cut is what got released, which already was its own form of a stripped down version thanks to all the filmed left on the cutting room floor to be stitched back later as SLV for those important late-night viewings in 1982.
(Oh yeah!)
The director's cut. On the plus side, it added proper exterior shots of VGER. The 4K shot of it is truly spectacular... but I'm skipping this from the 4K version because, on the minus side, they trimmed down a few too many scenes, and the replacement klaxon/alarm noises were utterly bizarre/downright annoying/rather laughable, which is impressive as I otherwise agree that the computer voice screeching the same condition incessantly was overkill. Yes, the ship is on red alert, you told us that 500 iterations earlier you stupid machine... That said, the pros just didn't outweigh the cons. It's easier to handle looping robovoice than the electronically altered sound of a goose in heat.
Bonus:
Wish that had been filmed proper back in the day. as it added uncertainty to Spock's character as well as being thematic..