Here is one way you could handle it.
Example:
each facility that produces a resource requires 5 million people (or break it up however else you want)
essential facilities that MUST recieve full work loads or don't work regardless require 1mil people.
special things can use whatever you want them to be and if they generate a bonus or something else that can be modified in a quantifiable way then just use the same basic method as described below and use 5mil per or set them as "essential" facilites that either run or don't at 1mil per.
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The planet in question has 8 facility slots
3 of which are used with essentials (space port, space dock, and something else)
These take up 1mil each so 3mil altogether.
The total population of the planet is 10mil outa a total of 20 mil.
So we have a total of 10-3 = 7 mil population to use.
We then build 5 mineral thingies so 5x5 = 25 mil needed to operate them at designed efficiency.
UHOH we won't have enough to run them all even at max planet pop. Lets see what that means.
at current levels we have 7 mil people to run 5 facilities that need 5mil each... Lets do it like this.
5mil people per facility is 100% efficiency but we only have 1.4 mil per facility (7/5= 1.4) and 1.4 is 28% outa the 100% that 5mil represents. So then we say that each of these 5 mineral facilities is running at 28% efficiency and thus only generates 28% of what they normally would after all other planet bonuses are applied.
Alter the numbers for higher population level and you get 20-3= 17mil for use or 3.4 per facility so 68% efficiency when this planets pop is maxed.
To cap that. Because I just know all of you are too stupid to catch that the first time through... or is it that I am so confusing... ah well.
First subtract pop needed by "Essential facilities"
Next look at number of resource facilities you have that need 5 each and break up the remaining population into equal little chunks and find out what percentage of the required to operate number each of these little chunks is and there is your operating value.
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Leftovers are unemployed or you could put in some other little bonus level on each facility like 5mil for 100% and a bonus 5% for every mil over that or just ignore it and assume the pop bonus for high level pops is doing that.
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Why I suggest straight values of 5mil for ALL resource facilites v 5 mil for mining and farming and then maybe 3 mil for research etc, is for simplicity. If you do that you start running into problems of dividing it up and needing 5mil for larger ones and 3mil for smaller ones and the number you have to spread around is 3.4... so do you break up the extra .4 on each of the researchers or what? It just makes it more complicated and to tell you the truth I just don't like it.
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