Adjacency bonuses, tile bonuses, planetary production settings, specialty improvements, planet classes, colonization events, all these create a terrific environment for highly specialized planets, whether manufacturing, research, or wealth (influence to a lesser extent). One would expect some increase in the required micromanagement to make near optimal use of specialized planets. But I contend it is WAY too much micromanagement in the current state of the game. I implore the devs to spend some time, after the first couple rounds of critical bug fixes, to make significant improvements to the workflow of colony management. Until then, I'm probably going to stick to generalizing everything on any map bigger than Medium, and I'm probably going to get bored of that quickly. That has implications on my intentions to pursue DLC and expansions. I assume others feel similarly.
I have detailed my preferred solution here. But there may be better ideas, so I'm willing to wait and see. The issues below all point to the fact that the planetary production wheels are a double-edged sword. I believe there is a large gap in micromanagement level between use of the civilization-wide production wheel and the planetary-production wheels. I believe having custom planet groups with a group-wide production wheel narrows that gap. I also believe some production wheel governors can help narrow that gap, and can be implemented in a way that allows the player to make the decisions, not AI. Whatever their solution, devs please explore some options.
Issue 1: Managing a planet through various maturity stages is micro intensive
When first colonizing a planet you plan to specialize, higher social manufacturing is appropriate. Over time as more improvements are built and population increases, it makes more sense to start specializing, while leaving some social manufacturing to continue working on the manufacturing queue. This means modifying each planet's production settings multiple times as it matures.
(Possible solution: production governor sets newly colonized planets to player-specified production settings, which switches over to a different player-specified production setting after a certain player-specified improvement is built. The user could specify multiple such production switch points. The final switch point would switch to the player-specified full specialization settings.)
Issue 2: Research, wealth, and military specializations require frequent production wheel changes as improvement techs are unlocked
The optimal production wheel settings for mature specialized planets is 100% to the specialized resource. But whenever a new tech is unlocked to upgrade improvements, some social manufacturing is needed to upgrade the improvements. For research, wealth, and military-specialized planets, that requires changing the wheel and sliders from the optimal setting to something that includes some social manufacturing. This must be done for EVERY affected planet. Furthermore, when the upgrades are complete, one must return the wheel and slider to 100% for every planet. Since planets finish their upgrades on different turns, this means micromanagement over multiple turns.
(Possible solution: production governors affecting planets individually to set production to player-specified settings during upgrades, and returns them to the player-specified full specialization settings afterward.)
Issue 3: Idle colonies and shipyards are annoying
Manufacturing-specialized planets are really military-specialized planets in the long term. So during non-upgrade periods production settings would be 100% military, as maintaining some manufacturing for projects is not as efficient. However sometimes it makes sense for a shipyard to be idle, for example when you have too much maintenance or you are in the process of researching the next tier of upgrades to ships and ship components. In such instances it sometimes makes sense to change the production wheel to some research or wealth. It is too micromanagement intensive to do this for multiple military-specialized planets, and then later return them back to specialization.
Issue 4: Rushing specific resources is micro intensive
Sometimes it is necessary to focus all specialized planets on wealth or research, even if it's very inefficient, for example if you need to save up for ship upgrades, get out of debt, or research a key expensive tech. When specialized planets' production is changed to start the "rush" you can click the reset option in the global production settings. But this wipes out the specialization settings, so returning specialized planets to their pre-rush settings is very micromanagement intensive as it must be done for each planet.
Issue 5: Tile improvement governors aren't enough
The devs have mentioned in streams their intention to create governors to help specialize planets. In context they seemed to be referring to governors that manage logical improvement placement to make good use of tile bonuses and adjacency. But this is not enough. Specialization governors also have to manage the planet's production wheel to make full use of specialization.