LFS is of course a must. No one should be diffing audio files via text haha!
Much of the long-project pain with Unity comes from its biggest limitation, in comparison to Unreal: no source, and so you're stuck with Unity's default behavior, limitations and bugs, unless you plan on extending it, wrapping it or replacing it. Whereas Unreal making source available doesn't lend itself to safe boundaries and compartmentalization.
Weirdly, Unity's irritation is also something of a strength, because those wrappers and replacements tend to find themselves on the asset store, often for peanuts. Often with source.
There's serious differences at the extremes, of course. But unless you're working with eight, ten, or more figures of budget I don't think it will matter that Unreal has superior tech in numerous ways, because you won't have the teams of artists to make use of it.