WHM Vs AST Healing Comparison at 50

[VitalSuit]

Does it effect the entire party, or is there a specific radius of the effect, similar to Cure III or Deployment Tactics?

If it's a small AoE, I don't see stopping DPS to group up to get a small DMG increase being that effective, especially since you've given up a previous (DPS) draw to do so.

It does have a radius but honestly in most groups you're going to be pretty close together so they don't miss those aoe buffs like Succor. If I see a BLM, BRD, or MCH standing at max range I usually yell at them because they get no buffs from either me or the WHM/SCH (although WHM aoes have much MUCH larger radii).\

Also don't misunderstand Spear. It's by far one of the worst cards in the deck simply because the only way to get any use out of it is to plan with the other players and that never happens. I either use it on myself if I need to cast a long cooldown skill (Aetheric whatever, our Shroud of Saints skill) or I Royal Road it for the AoE buff.
Basically the way it works is Spear lowers the cooldowns of your abilities (those skills off the global cooldown) only if you have the buff on you BEFORE you use it. if you already used the skill and then get spear on you it's a waste because it does nothing. That's why it's considered worthless.

Nothing from arc = wtf my virus T-T

Yeah we have Disable which is only used for tankbuster skills or party wide AoE and since it only affects the next attack it's pretty dificult to land it properly.