Abundance: Professional

I just solo completed this achievement with well over 10k score without using any profession. I tried other methods like gathering herbs in Herbalism Grotto but I could never get enough. Here's how you can do it:
Go to the Skinning Den in Zul'Aman (make sure Abundant Harvest is not active there).
Don't join any group. The emptier it is, the easier it will be.
Kill 25 beasts and skin them. You do not need Skinning to do this. There is also a bear that you can skin multiple times before it despawns.

This method was a lot easier than competing for nodes in a full raid group.

I found the best way to do this achievement was in Floaret Grotto, Harandir. Go to the section of the cave with Floaret buds (the section with a deep pool with buds at the bottom) and just keep interacting with them until the event ends. They respawn super quickly and you won't be out of buds to click. I got this first attempt using this method after trying multiple times in Eversong. You do not need to have specific professions to do this achievement (completed with LW & SK) and I was able to complete this achievement in a full raid WM off :)

Head to Harandir (Herbalism Grotto) and go to the bottom of the cave where the water is.
Click the herb nodes 25 times to complete the achievement, Herbalism isn’t required.

There are several nodes in and around the water, and they respawn very quickly, so it’s easy to finish in just a few minutes.