I think the main upside of the gimmick was that it was optional. Lemmings Revolution basically had
all levels wrapping in a Lix manner. If this got introduced into regular NeoLemmix as a default, it would distance it even further from regular Lemmings - while at the same time making it more similar to Lix, instead of having two different games for two different purposes.
I definitely enjoyed the gimmick with both the vertical and the horizontal wrap activated, so I'd be the first one to appreciate its reintroduction!
Granted, in order to create Lemmings Revolution-style levels, you'd need to have the option to switch on horizontal wrap only without automatically having to activate vertical wrap as well.
So it would probably be best to make both independent, like back in the day, as long as it is clearly visible to the player whether the wrap feature is active or not - I clearly agree with IchoTolot here!
The main annoyance about gimmicks was their surprising nature, i.e. the level creator could activate them without the player's knowledge, thereby potentially wasting a lot of the player's time with guesswork.
Maybe present some arrows at the edges of a level at the beginning, together with the arrows below the hatches that show in which directions the lemmings are going to come out?
The main effort in re-implementing the wrap gimmick would probably affect the fencer and shimmier, since those skills didn't exist in NeoLemmix back when gimmicks were a thing.