I like the "new slider" too. Unless it is too sensitive so I will be unable to move it in a straight line.
Well, on the other hand it is only half of the picture. The other half is the specialization on planet level. Let's see. I assume the switch is still immediate, does not take time as in Haegemony.
I do like the look of the new slider, I just wonder about whether it's a mechanic that should stay in the game.
If the mechanic is kept, The one thing I'd want with the new slider, is the ability to enter in and lock values manually, otherwise I can see it ending up as frustrating. I'd also want it settable by planet (would help the AI as well, it's one of those things AI beats players at) There really needs to be a balance between AI utility, micromanagement, and fun. Messing around with the Econ sliders in GC2 wasn't much fun.
Another thing I want as an option- I want players to either start on that screen to set their sliders first, or be able to set the default slider in the main options, to cut down on something to remember to do in the first turn. One plus of LH over GC2 is that turn 1 you don't have to mess around with a couple of screens before starting to play.
Personally I never liked planet specialization being handled the way it was in GalCiv II, felt limited/silly/gamey. You specialize a planet by building stuff.
As a new mechanic, I wouldn't mind governments being able to force min spending amounts, and I also want all-factories/all-labs to not be all that viable as an approach.
I'm honestly surprised you kept this mechanic, I figured you were going to dump it, and was hoping that was the case.