I played through the Empire route and really enjoyed it, though it did feel kinda short and the last two battles were balls to the walls nuts. I really think the strongest point of that route is the characterization of Edelgard, which playing the church route next makes me feel conflicted about betraying Edelgard... Also having seen the insanity not very deep beneath the surface in Rhea makes this kinda awkward
The church route feels a lot easier than the Empire route too.