I have been using Skytest and real wildlife and immersive creatures. I have been finding that the plains in the whiterun hold are WAY to populated. I have been seeing herds of as many as thirty or more elk together with a bunch of sabre cats all over the place and its to the point that the game tends to lag like crazy from time to time. What gets me the most is that a lot of animals dont seem to have scripts, like they stand there and let you come up to them. One time a pack of sabre cats caught me by surprise and I ended up running into this large herd to try and throw them off only to have the elk do nothing and have all the sabre cats chase me through it like a maze...

All three of these mods does something unique that I dont want to lose so I dont want to get rid of them, but if there was some way to make the game balance itself out according to what my system can handle...

And yes, I am using those enhancers, ENB and so on, I put all those in but im not sure what difference they make...

This is a known issue mentioned on the SkyTEST nexus mod page. From memory, the game engine is incapable of running more than a certain number of AI simultaneously. Are you using Skyrim Memory Patch? That might help...

I believe Skytest needs compatibility patches for the mods you have.

First do you have those?

Second what version of Skytest are you using?

Depending on your version of Skytest there is a patch that only gives the AI and removes the extra spawn points that are included in the original mod.

The author of http://www.nexusmods.com/skyrim/mods/9778/? has admitted there are problems with the mod & has abandoned it. There is also a http://www.nexusmods.com/skyrim/mods/46495/? which may solve your problem.