Patch 1.7 is generally considered to be the Hunters' Golden Age. Its been downhill every patch since then. As far as what you missed, Hunters used to get 2 RAP from 1 Agi. Now its 1:1. They made up for this by taking a chunk of Agi off of what was considered to be "Hunter gear", and replaced it will what would have been an equal amount of AP. However, we still lost Crit, Dodge, and Armor because their adjustments weren't really up to snuff in these areas concerning Agi.
What I meant by my comment was that you don't see the AP adjustment on any gear under 60. Compared to what Hunters got from Agi pre-WoW 2.0, you do alot less damage 1-60. Also, I don't think you should worry all that much about speccing out of BM at 60. There is a ton of solo work out there for you. Granted, I did 61-70 MM/S, but I had been BM when I first leveled 1-60 in 2005. If I were leveling a Hunter these days, I'd most likely run a build such as this.