Which custom ROM is least resource hungry?

[asim.sidz]

I am asking for opinion from people who have used custom ROMs for the Moto G5s Plus. I tried the AOSP Extended 8.1.1 custom ROM but I found out that it uses a lot of CPU and RAM resources in comparison to the stock ROM, while my aim was to migrate to a lighter ROM so that my phone operates quicker and more battery is saved. Any valuable input will be highly appreciated.

Thanks in advance.

 

[sensi277]

Stock ROM + Greenify.