This mod has some side effects, it alters the stack size of several items (to like 2000, too much), and also affects the base amount of requested items (to 10, no matter the stack size)

and it also makes the game go really slow

really slow? it should not have much effect on UPS, cant imagine why it should go slow. There are no functions running every x ticks or anything AFAIK. Can you elaborate your claim? Maybe with some debug info of your UPS usage?

regarding the stack sizes, every stack size will be multiplied by the value in the mod settings. So if the original mod sthing had a stack size of 200 then it will be indeed 2000. For the request amount i will add the option later that the value of 0 will not alter the default request amount.

I also checked that big bags indeed does NOT run any code while the game is running, it only applies patches to prototypes while loading. So definetly no effect to UPS.