In PvP this is going to become extremely important, because A) Spell-weaving drains Stamina over time and B) Our one fail-safe method of escaping melee range is to sprint away - something that also consumes Stamina C) Active blocking is yet another stam. Drain for us, but it can save our vindictus gold bacon if it keeps combos for hitting us for max damage.
You won't need to dump points in asap (unless you find yourself sprinting a lot) but it's something to keep in mind for later levels for sure. The gear that adds +cc I mentioned above can help shift some points here if needed.
Climbing: Not excessively used, but in some places it may be a necessary evil. The early destiny quests will require at least 1 point spent, and there will be some places later on where you might need more than that, though again, it's nothing excessive.
A good bit of the cloth armor I've seen has + CC on it as well, so that can help once you reach higher levels and a lot more of the skill options become available.
For example only having 50 points out of 300 in some places will be plenty (climbing points should give an on screen message letting you know if you don't have a high enough skill / how many points you need in it).