I feel the same way, friend. I never disliked Rarity, I was just not...how do I say this? Uh, I wasn't that into her until I watched this episode. After that, she went up on my Favorite Ponies list. Love Rarity. <3 BUT Applejack♥ is still my fav ;D
I know how you feel I didn't like Rarity when I first started watching the show last summer either but now she's my favorite Mane Six pony.
I never did dislike Rarity. For a while she was behind Pinkie Pie for my favorite pony but episodes like Green Isn't Your Color and Sweet and Elite bumped her way up. Those and Suited for Success (which I didn't particularly love but it's still relevant) I feel really showed her element of generosity; she may act stuck-up most of the time, but when push comes to shove, she always cares more about her friends than herself. Which only kinda showed in this episode. She did agree to go on the camping trip when she didn't really want to, just so she could spend time with Sweetie Belle. But... packing a freight carrier's worth of gear and then making that same little sister haul it? That's way out of character.