Personally I would start with a couple of mods. DarkWraith's UI Mod and also his great mod for AI ( the stock AI sucks ).
Both of these are in the SH5 Mod's Forum. Check out the thread for each, read up on them and go from there. If you don't have JSGME ( Mod Enabler ) there is a nice " how to " guide for it below my signature.
JSGME Thread ( to download the App. ):
Here
DarkWraith's UI Mod:
Here
IRAI Mod:
Here
There is also a Mega-Mod out, but I would try some of the smaller ones first, then once you get comfortable , try it.