Both depth and variety can be found in all packs (you can't have 0 variety or 0 depth) but I would say that what I have found lacking is depth. Variety can often be achieved with the tools that the game is providing to us and Maxis are also creating a lot of variety by adding a lot of content to this game.
But for me content that have more depth gives me more motivation to use it and therefore create variety, when I get a lot of variety but I discover that there is not much depth to it I lose interest in playing. The packs that I liked the most had both depth and variety to them but I often ended up liking them more because they had game mechanics that had more depth and made me interested in playing them for longer.
It depends a lot on what they chose to focus on in the pack. I never thought that I would like Dream Home Decorator but I really liked it because they focused a lot on making use of the likes/dislikes system and you could renovate any lot in all of your worlds. I thought that I would like High School Years but I really disliked it because they didn't focus on the actual High School, instead there was some depth in creating outfits on Trendi and other things.