Origin does have sales a few times per year but they always seem to be structured differently, they aren't always % offs across the board, and they don't always include the store worlds. It's pretty impossible to predict when and what the next sale would be. Sim Points themselves never go on sale, I believe that they can't because they are regarded as "digital currency."
I have DV and although relatively small, it's one of my favorite worlds. Love the baby dragons too, but I only let very few select sims in other worlds have them. Anyone can pick up a violin and start learning to play it or do archery, though I understand those two items are available as standalones now as well. My sims use it as a Traveler mod vacation destination and I've moved some of the interesting elven inhabitants to other worlds to see what happens when they breed with the locals and their genetics get spread. I also have RH, must have gotten on sale myself somewhere along the line, but have never visited or loaded up a game there. It's on the "To Do" list.
