To add to that list;
[Shield Bash] Because it requires no skill whatsoever to beat someone with no skill whatsoever, but if you're going to use it effectively, you need to be watching your opponent and trigger it, say, in the middle of an attack.
[Frenzy] For reasons explained above, good in the hands of a good player, bad in the hands of a bad player, as they won't cancel it when they're taking damage, prekite, etc...
[Resurrection Signet] For obvious reasons. Use it once someone dies. Everyone can use it. With it's prone-to-interruption cast time of 3 seconds, more experienced players will get out of range of mesmers (if possible) and use terrain to prevent rangers; from interrupting and/or disabling it.
[Power Drain][Leech Signet] These two skills are very balanced, giving you either a defensive or offensive role in interrupting skills, as well as providing you with energy. If you're not good at interrupting, you're wasting skill slots and/or wasting precious energy. You might want to go with the easier to use [Glyph of Lesser Energy].
[Mind Shock][Shock][Gale] All of these skills must be used in moderation for them to be effective. Not enough usage means a wasted skill slot, too much usage means a grayed-out blue bar which will hinder your capacity to do anything. Knowing how to balance: the time remaining in a match, skills that need to be interrupted, movement on the field, spikes, exhaustion, etc.. are all key in using these skills perfectly.
[Dash] In my opinion, THE most balanced skill in the game. It will kill your energy if you spam it, it only results in a net speed buff of around 20% faster, and it can be used either defensively, offensively, to trigger traps without taking damage, strafe fast moving projectiles (or projectiles at close range), break aggro (in pve, also Lolbalance in PvE) and more.
There's my opinion.
