For the absolute cheapest, I would go with Bamboo. But I recommend Intuos4 or greater for a mid-range, all purpose tablet. However, the Cintiq is the ultimate, and I've been saving for one of these (unsuccessfully) for a few years now. I think a good compromise between price and quality is the Intuos.
The Bamboos are still pretty small, but have a bit more functionality than they used to. Newest lines have the multi-touch feature enabled, like the Intuos5. If you're really hurting for cash, it's a good place to start, and I think it's something to consider if you need something portable, and don't have/like anything like the Inkling or the Galaxy Note.I haven't looked at Wacom's offerings in a while, but from what I recall, the Bamboo is fairly small, with about a 3x5" drawing area. The difference in day to day use between this and a 5x8"ish Intuos tablet is tremendous. The bigger tablets have programmable buttons right on the pad which helps useability too. Again, the specs may have changed some in the last few years, I just want to make the point that a (slightly) bigger work surface makes a much bigger difference than you might otherwise assume.
It's your brush settings. IIRC Shelley is an expert with those tablets. Best to ask her questions you can't find answers to on the web.