if you don’t need dynamic scenery you can still bake lightmaps
You are millions of year behind in recognizing the problem if your still suggesting lightmaps. There are a plenty of bakeable indirect approaches than just lightmaps that support moving lights and basic object destruction. Unreal just doesn’t support them.
You’re stuck with
Lumen, expensive and has visual issues.
Skylight+DFAO looks terrible and has visual issues.