1.Sliders are faster and easier to precisely dial arbitrary sets of asymmetrical values. ( ex: 22%, 34%, 44% )
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This is only particularly true if the sliders can be locked. Otherwise, you're stuck fighting to get it to about the right area to start with, and the fine-tuning can be a bit of a pain.
2.Wheel is faster ( and arguably easier ) to dial Symmetrical sets of values. ( Ex 40,40,20 ) or Polarized values ( where one is 0% )
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I disagree with this one. Anything on the border of the disk is easy to set, but things on the interior of the disk are more difficult to set precisely. The disk's advantage is more that it's easier to set things to approximately the value that you wanted, and approximately is usually good enough unless you're being anal. Symmetrical values are slightly easier than arbitrary values to set on the interior of the disk, true, but I wouldn't say it's particularly faster than sliders, nor would I say it's particularly easier than sliders; it's just a test of fine motor control.
Personally, I think that if you wanted the best of both worlds you'd put a lock on each axis of the disk and have a little +/- button next to each. Then you could set the approximate value you wanted quickly, make a fine adjustment along that axis if you cared to, lock it, and then adjust the other two axis along the arc described by the locked setting. Also nice would be a numeric entry field for each axis.
But that's mostly academic from my point of view, because I more or less use the disk as a three-state switch. If I'm building something, everything goes to production (unless I have the cash on hand to just rush whatever I want to), otherwise everything goes to wealth or research as appropriate for my current needs and the improvements built on the world in question. Given how heavily the game encourages planetary specialization and given the ability to set production distribution on a per-planet basis, I just don't really see the need to have anything but money improvements on purse worlds, labs on lab worlds, and factories on factory worlds, and even a low-class planet like Mars decked out with Markets and set to Economic Stimulus can easily pay the maintenance bills on a decent number of ships and research and factory worlds, especially if it has a decent number of tiles adjacent to one another.