My drive is SATA, but it is a 500GB MX200 so it can't be that slow. Sadly that is all my motherboard supports and I won't be buying another SSD for some time. As for RAM I only have 8GB, so I am not sure if a RAM drive will be ideal. It does seem like you have to brute force the engine and the game wasn't that great so I may just uninstall it. I will say that ArmA 2/3, while still unoptimized, both run far better than this on my PC.
I will note that I do have ArmA 2 installed on an HDD and can use my ArmA 2 units in Take On... so is the game loading some files from the HDD? I am not sure if it copied the files over or just uses the ones in the ArmA 2 install. That may explain the horrible loading issues.
I think Take On is a whole separate install; so it shouldn't need\use any Arma2 files by default.
Have you monitored your SSD xfer speeds while running the game? You can also double-check to make sure it isn't (for some reason) running from the HDD. You could also check for any firmware updates for the SSD as a last resort.
I don't play Take On; but I've played a lot of Arma2\3 and since I've used an SSD I've never had texture or LOD popping