This one took some thinking, but the catalyst was provided (once again) by
arabian . I know I'm starting to sound a little like a broken record with that statement, but I like to give credit where credit is due :o) Once I had the seed planted, it didn't take much to mold my thoughts into this answer.
Day 27 - Something that you wished happened but didn't
2 x 09 Katerina - Damon and Elena at the front door of the Boarding House
My idea for this scene:
Instead of brushing past Damon with her puss-face on, Elena takes the time to meaningfully and sincerely thank Damon for rescuing her from her kidnappers. Mentioning that deserted mansion prompts her to remember that Elijah had ripped her necklace from her neck. She wonders out loud how she got it back. Damon tries to mask his reaction, and feeds Elena a non-answer. She recognizes his diversion and they share a wordless moment. This in turn brings to mind her reaction to his (unheard) declaration.
The whole thing wouldn't take much time, but would give some (much wanted) satisfaction to DE fans. It wouldn't interfere with the overall theme of the episode but would add a lot to it.