They definitely don't fail. I think the "epic" and "grand" sound came more from your imagination than from the actual theme, because I never got that feeling from the original, and that is my favorite theme from ALttP. Upbeat, and exciting? Absolutely. Epic? Definitely not. And Lorule 2 definitely feels grand, unlike the original. That's not why it's better, but it definitely lends itself more to a larger scale than the original.
Well compare it to the Lorule 1 or the Brawl remix and you'll find the "epic" in it. Compare it to Lorule 2 or some Smash 4 remixes (or pretty much any fanmade remix EVER) and you'll find the upbeat. It had both.