The extent of my knowledge of SM in Paris is limited, but I'll assume it's a great ride.
I'll also assume it's a very natural fit for its land. In fact, I know it is.
For me, to justify Guardians in Epcot (barring a storyline that somehow relates to celebrating human endeavor and culture... which there's about a 1% chance of), the ride needs to be Top 3 in Orlando. And cutouts and a few projections aren't gonna get that done for me. If you're going to further compromise Epcot, you had better blow the damn doors off.
But that's just me! I recognize we all have different things we're looking for.