There was a bit of chat on this over the weekend, but I wanted to get it up here as well.
It gets very frustrating when you don't have a quest to work on and apparently no good way to earn a lot of XP. At the earlier levels, I was patient enough to pet and water hundreds of times. (I also had a garden growing, though that takes time to grow.) But since the level ups require more points for the higher levels, this is not very effective.
One of the facets of this is that I'd gone deep in gardening, and then started Animal Kinship. But the quests for the early skills don't reward with many XP, so as I was working on Animal Kinship I was earning XP at maybe a Level 3 rate, although I was Level 12. There needs to be a way to earn XP at a Level 12 rate.
I think this is just a nit with the current status of game development, and the upper skill levels are less fleshed out than the rest.