Happy to go to bat for this one! I think Rarity was a great choice for a straight man here, because she has an eccentricity of her own, but it's brought out by the stuff she doesn't fully understand. Usually, her response is either to turn up her nose or (even funnier) try to go along with it and take every bit of it seriously.
As far as when I like drama and when I don't, I'm sure I've been more positive overall when it's more subtle and not the whole focus, since that usually stops the team from overdoing it. But I did enjoy episodes like Party of One, Hearthswarming Eve, Hurricane Fluttershy, Flight to the Finish, Tanks for the Memories, and The Mane Attraction, so I'd like to think I can enjoy straight drama too. (In fact, Winter Wrap Up and Canterlot Wedding are two of my favorites.) I guess I just feel like drama should come from the story, not the other way around. If an episode seems like it started out just wanting to be dramatic, so the characters go through maximum tears and anguish and "touching" revelations, regardless of whether the story they came up with is anything that should ever lead to that, I'm not buying it. In fact, it feels condescending, like I'm just such a sap head, that all I really want to see is characters "like me" being validated in the most dramatic way possible.
Why not go wherever your story actually would lead? (Or should?) There might be fewer tears, but they'll feel more real.