I have a feeling that this area of the game will become more developed/nuanced once the more complex empire management screen is in (it was discussed somewhat in the last dev stream). It should make switching focus for specific planets easier and ease the amount of micromanagement, I agree that at the moment it is a hassle to go through each planets production wheel screen to make changes.

In the current beta I have also rarely used the global production wheel but like the option of having it in case I ever have an emergency situation that demands an empire wide switch in focus, I have a feeling it will become less useful though once the aforementioned empire screen is in.

I have found myself making incremental changes on the individual planet wheels though. I do seem to make more dual focused planets generally unless I have a specific reason not to so feel the need to balance stuff like happiness, wealth and research more than if I had single focus worlds.

I have never moved the planetary wheel, because managing by planet has always been much better. That said. I am currently 300+ turns into a game where I am specializing all my planets in population and keeping a balanced economy. It is going well and I can see using the global wheel in this game, though I have chosen to keep it balanced the whole game so far.

I need a planetary screen where I can see the sliders of all my planets as the micro can get nuts at times.

Perhaps let use have sliders "designer" (like the ship designer) where we setup basic manufacturing, research, wealth and production (improvement vs fleet) so we can just choose those to switch around instead of having to go planet by planet, hit govern, move sliders, go to next planet, rinse and repeat.

So I can have a set of war sliders and peace sliders for planets.

i think the main reason why not many people use the wheel is that generally there is no need to have large empires atm (default war starts) also the other options there are not available. wait until the other options come in and when there will be some requirement to use the window. i agree with the OP when i did use the wheel i pretty much just 100% one side that i was specializing in. i think that as you make adjustments away from the 33% each focus. that there should be small detrimental impacts on the planet based on where you are shifting focus. as an example manufacturing focus makes your population happier although reduces population growth and influence, research focus increases influence at the cost of happiness and growth, economic focus increases growth but decreases happiness and influence. the same type of bonus/penalty should apply when the manufacturing is skewed to one side. probaly the best way to balance it would be based on population difference. greater the gap greater the bonus and penalties.

with a system like that it adds meaning to the choice a player makes. as it stands there is a small meaning but it allows the player to exploit a population. even slaves perform less efficiently when they are oppressed. Forcing a focus for a planet would have consequences and benefits taking a look at our wolrd earth. we a generally economically driven look at the positives and look at the negatives. taking it to the game if you want to specialize in a aspect there should be a consequence for the action. 

on the flip side with the example above it would make for some interesting games. as setting up research fringe worlds bordering enemies could be used for influence creep and with the right ideology (persuasion) could be interesting. ofcourse playability would have to be taken into account. 

This is one feature I have not tried/tested and possibly won't ever use or alter from the default value.  To me the way you specialize planets is by choosing what improvements you want, or probably just by trying to make the most of Hex/Tile Bonuses and Adjacencies.

Perhaps it may be needed when the game becomes even more complex once Frogboy's AI routines kick in and the game becomes more fleshed out with more features and less disabled techs/Ideology but until then . . . . .