I'm a brand new AFOL this year. I got my kids a few sets for Christmas and we ended up having so much fun with them. I started collecting a few sets just for myself and a few more for the kids and I.
My personal favorites so far are:
1. UCS Slave 1 - It is astounding to me how well designed this set is. It was a really fun build It is also a work of art when displayed on it's stand. Even though it's a UCS set I still chase my kids around house with it, although I have to hold it with 2 hands on the red base. I think i'll pick up another copy and leave it in the box.
2. Wall-E - Cannot say enough good things about this set. The design is incredible, it looks amazing on display, it's incredibly posable and very expressive. Star Wars is my primary interest in Lego, but this is such an amazing set. Nearly perfect set!
3. Imperial Shuttle Tydirium 75094 - I love this set. I would love the UCS version of this, but I don't have space to display it, nor can I afford it, so I bought the 75094 set and heavily modded it to look much more like the UCS set. The size is perfect for me, still looks fantastic, but small enough to play with my kids.
4. Exo Suit - Another Lego Ideas set that is really excellent. This one surprised me. I like it even more than I thought I would.
5. AT-DP - This Rebels set is excellent. I'm mainly a fan of the OT, but this is such a well designed set I had to have it.