In my opinion, the worker count is not actually all that important – what is are all the shifts to the other units that happened between end of HotS and start of LotV.
If you actually want to change mid game, you need to change things that change the mid-game.
Humor, for a second, if there were no changes besides the worker count. This is a huge overhaul to the beginning of the game and all openings, because all of them are built around 12 workers so the rug under them is all gone.
But, “mid game”? That’s after you’ve saturated your bases. If there were no changes to the game besides starting workers, that can only affect the play pattern of the beginning of the game.
Humor, similarly, if we had all the changes except the worker changes. The mid-game state – the ebb and flow of economies after the 3-4 minute mark, the units you can and want to build, etc; are all the same as they are in the current 8 worker start. But you get to that point faster, because there’s less initial dead time.
The reason WoL/HotS had different mid-game states is because of the amount of baseline abilities and the actual unit balance was different. WoL Siege Tanks need the Siege Tech upgrade! That stymies tank push timings. But with the 12 worker start, siege tank pushes didn’t need to be slowed down in that way, so the ability became baseline. With the 12 worker start, things kicked off faster - So to supplement that, Stim and Combat Shields research faster, Reaper rework, Adept exists, Hallucination is baseline, Ravager exists.
These are the things that so hugely change the way that the game progresses and feels, not the worker count.
If the problem is cannon rushes, just increase the build time of cannons. Cannons that are built don’t overperform, it’s that building cannons generate HP too quickly to be nicely dealt with except by pulling enough workers that it hurts the economy badly.
Increasing their build time only would be a meaningful shift for near-GM players who rely on near-exact second timings for counter-buildings, and that’s the sort of situation to which my only response is “tough”, y’know?
If the problem is other types of proxy then I don’t have a suggestion though; I don’t really think they’re problems but I don’t play-play 4v4s (there’s just too much, it’s brain-off for me)
But on 6 workers, each cheese response was more razor-thin. Both players were subject to the same painful margins.
¯\_(ツ)_/¯ And I don’t see how that doesn’t keep forward for higher players (it certainly still is true in 2v2)