Best overhaul mod

[The Vlach]

Is there a top overhaul mod for EU4 that revamps everything especially missions etc?

CK2 was known for having some elite overhaul mods but EU4 never found any myself

[Totally Innocent Chatbot]

I've not done any dabbling in modding myself, but the mods in the "Flavor Universalis" and "Vanilla Expanded" families are popular options that would likely do some of what you're looking for. Probably don't want to mix and match the two though, that would likely have some compatibility issues.

[Hunkthebear]

Depends what you are looking for, If your looking for Vanilla+ like CK2+ or similar you have the Expanded Family of mods and things like it. If your looking for more timelines on the same map you have Several Roman mods, and the Extended Timeline mod (goes from 2Ad-9999 or something. but mostly has content up to just byond the modern day)

If your looking for Focused overhauls you have things like Voltairs Nightmare which focuses exclusively in Europe on the HRE and regions around it. Im sure there are more out there as well...

If your looking for TOTAL overhauls i cannot recommend Anbennar enough... It has Magic, fatasy races (Orcs, Gnomes, Dwarves, etc..) and basically tries to answer in a serious fashion how would a DnD world react to going through the Renaissance to Imperialism age. But there are others out there like a few Lord of the Rings mods and i think ive seen some Fallout and Avatar Last Air-bender mods as well.