Honestly, unless your a Shaman...Dragonscale really isn't that great. If you insist on staying with leatherworking I would suggest going Tribal or Elemental. Now Elemental can really blow because the mats are extremely hard to come by, but if you can pull it off you can make a good amount of gold. However with Tribal, though you will not benefit much from the items you create you can always sell your profits to Druids and that isn't so bad either.
Personally, I have a level 60 Hunter who took up Elemental and mind you once you choose, even if you forget and decide to turn back to leather you will always have to go that route, you can't ever do anything else. I decided later to just blow it all to the wind and take up mining and engineering. And being high level helps speed up the process cause I can go just about anywhere with no problem and build mining. Just a suggestion. I'd ditch leatherworking altogether and either take up mining/engineering or I would just go skinning/mining and sell everything for strait profit and start savin up for that epic mount.
But in the end it is up to you. To break it down here are the benefits as I know them.
Dragonscale: Great for Shammy...not so great for hunter, though some gear has some decent stats, at level 60 your gonna blow it all out the window anyhow when you start for your beaststalker set.
Elemental: Lots of farming and work but the end product will get you some decent gold if you farm everything yourself and don't spend an outrageous amount on the auction house for your mats.
Tribal: Can't really use the end product since by now your into mail anyhow, but some great stuff for Druids and can turn a decent penny if you work it right.
Engineering: Jumpercables...Deepdive Helm...Lots of fun toys...Besides what's better than the hunter who 90% of the time is the only one who lives in an instance, busting out his jumpercables and ressurecting the Priest so nobody has to run anywhere? (That is if you get the one out of 80 times they actually work, but it's better than nothing right?)
Mining: Money Money Money and needed for engineering but even without engineering...Money, Money, Money (One step closer to Epic mount for every stack of Iron/gold/bronze/tin etc that you sell)
Skinning: Money Money Money and needed for any kind of leatherworking. Any kind of leather guaranteed to sell if you price it reasonably enough because all proffessions need leather.
Hope this helps. Safe Journeys =)