I just fished from 1-300 on the wrath beta and it flew by it seems. I didn’t track how long it took but it was far less painful than doing it in TBC.
The fishing time reduction was the biggest thing. Also not needing to go do the quest was a nice time save too.
I highly recommend getting a bunch of the best lures (hooks) and flying around and getting pools in Zangarmarsh until 325 or so, then heading to Terrokar lowlands or Nagrand and doing the same until 350. After you hit 350, try getting the pools up at Skettis and above the Horde area in Terrokar (Highland schools) so you can maybe get a crawdad pet.
The pools will give food you can maybe sell (or hang onto to skill up cooking on your dk). Motes and scrolls are useable too.
To add to this, while you can level fishing from anywhere regardless of skill, it’s still recommended to fish in certain spots if you plan to level up cooking as well.
Yes fishing 1-375 is faster in wotlk. It slows down again for 376-450.
A big part of the reason it is faster is you dont have to move around to new spots, but the chance per level per cast is also better. You can still have bad luck and go 10+ casts without gaining a lvl similar to making multiple green skill rank items in a profession, but its not as likely to not gove a level.
I believe fishing is broken. It is taking me precisely 10 casts to gain each skill point regardless of what is caught (Including weeds, driftwood, fishing line, etc). Catching actual level appropriate fish does nothing to accelerate the skill point gain, so if you need 50 points you will be doing 500 casts, and it doesn’t seem to matter where you fish as long as you meet the level requirement.