I really enjoy generation 5. In fact, it happens to be my second favourite generation (after generation 4, of course)! Initially, I wasn't a fan. My distaste for the anime tainted my view of the games. However, my opinion on gen 5 has since changed. While I consider Black & White to be weaker main series games, Black & White 2 are some of the best entries to date. They're riveting, full of twists and turns, and wonderfully dark. I love how story-based generation 5 is. Furthermore, I love the Unova region as a whole. There are an endless amount of quaint towns and bustling cities to visit, overall it's by far the most diverse and unique region we've seen. It truly stands on its own in terms of its wonderous geographical design. The characters are also phenomenal. Cheren and Bianca are probably my favourite rivals, I especially adore Bianca's sheer exuberance. Team Plasma is also a really thought out team, and an immensely menacing one at that. Their goals are clear, purposeful, and vastly different from all previous teams. Dare I say that Ghetsis is the most gruesome evil-team commander yet, he makes Giovanni look soft. (Also, we can't forget how swell the gym leaders are! Elesa in particular, she's one of my favourite leaders of all time. A truly electrifying woman indeed!)
Most importantly, generation 5 pokemon are incredible. Many of my all-time favourites were introduced in generation 5, including: Liligant, Chandelure, Samurott, Serperior, Liepard, Cinccino, Swanna, Gothitelle, Zoroark, Whismsicott, etc. (Only generation 4 provided us with better pokemon designs, in my opinion. It's super close, though.)
Gens 6, 7, & 8 have nothing on generation 5.