Guild Wars 2

We all know that there are “rich” ore veins, I suggest that there be “Thick” tree nodes that offers equal material chances as its “rich” counterpart.

This has allready been discussed. My answer is no.
The reason is that there is no need for it. You are right that there is an absense of ‘rich trees’. But wood is only used in the production of weapons, where ore is used in weapons, armor and jewels. Besides that, there are more tree nodes then ore nodes. The presence of rich ore nodes is to make up for this.