Use the planner to test a route and its assumptions; do not read the preview nodes as official launch values.
Three trees, one character
Race Tree, Class Tree and Archetype Tree are the three progression layers. The recorded development scale is roughly 230 Race nodes, 230 Class nodes and 80 Archetype nodes—500-plus nodes in total, not a promise of final counts.
Points force a build decision
The source records a Level 25-era estimate of roughly 60 skill points, meaning a character can only unlock part of the full board. Plan around a small number of defining nodes instead of assuming every branch will be completed.
Node types change what a build means
The public node language includes attributes, passives, Spells and Spell Modifiers. A Fireball build is therefore incomplete until its modifier direction and the supporting Race, Class or Archetype nodes are known.
Branch-jumping is a route, not a guarantee
Archetype Trees are described as several adjacent branches with multiple Spell tiers. A player may jump between branches for complementary spells or modifiers, but the source explicitly says the pattern will not suit every Race × Class combination.