I wrote the above using the good information/ideas other people had already put in place. Its hilarious to me how clever the people were who broke this down years ago. Way ahead of their time haha.
So the real question is - what % rates actually matter.
-My understanding is 15-17% trees are essentially identical - especially if you practice them to the high 90s.
-I believe you need 20 STR to hit the 18% tree on a warrior. So only trollocs can hit this.
-16 STR tree opens up the 15% pathway for female channelers. This provides a substantial practice advantage.
-The 18% hunter tree is almost unattainable. You have to essentially have near perfect Illian stats. Warriors would likely benefit from this tree the most since each saved practice equivalent is worth 2.
-Warriors can hit the 18% tree for rogue practices if they have near perfect physicals + high enough int or wil. So for example 19 17 11 19 17. The benefit is very nice because the practice equivalents are worth 3 a piece, but ultimately the value isn't world changing. If you were going to practice dodge or attack to 93 you save 2 equivalents (6 practices). The benefit of a clan practice bonus is probably more significant.
-Hunters can also hit the 18% tree for rogue practices thought he value is diminished because each equivalent is only worth 2.
Now, all of the above is written from the perspective of an old rich, bastard. If you are still slumming it and counting up your 12 vs 14% trees. Yeah, these trees are rough. Where you'll really see this is with trolls and the hunter practice tree. If you can hit 15% - heavenly. You'll essentially be practicing like a human. However, you'll need 19 (int + wil = 23) 18 x which is essentially about the max of the wolfish homeland.