I don't know if anyone else has done this, if not, it might be a good idea to try it out as i feel that it's helped me a lot when it comes to getting new soldiers.
I'd recommend completing the game first, try to get stealth and unlimited ammo bandana to help you out. Take out 3 of the 4 enemy skulls. Get to code talker, once you have him, leave him in a safe place from enemy harm, then finally take out the 4th skull waiting for you.
Once you take out the 4th skull, the hundrends of enemy soldiers that where in a zombie state will be stunned through out the rest of the mission. If you have completed the game, many of these soldiers will have an S or S+ rank. Capture as many soldiers as possible as this will help you boost your mother base a lot faster than going around free roam capturing a few soldiers unlike a couple hundred. Make sure you capture the soldiers from the original starting point of the mission and the other extraction point in the other direction. I must have captured at least 70 soldiers in that mission alone that had enough S rank skills to help me out when it came to getting my mother base facilities higher than normal.
Once you captured them, make your way to the LZ and finish the mission. Make sure you keep Code Talker with you at all times, that way you don't have to go all the way back to get him if you go to far.
I'm sure other people might have done the same, but if not, its worth doing it :)