[FA (and O)]Picking Druid specialties

[CJNyfalt]

I'm going to play a Druid in FAAngband, and I'm have trouble picking which specialties to take.

The first tier candidates:
Power Strike - It's good in the beginning, but will it become useless later on?
Harmony - Better staying power is good
Channeling - More power on first strike
Clarity - +2 to spellcasting stat and more mana is always good.
Meditation - And so is faster mana regeneration
Regeneration - and ditto for hp

Second tier choices:
Beguile - I haven't been sold on slow, sleep, confuse, .... even if they are better in FA & O
Enhance - I also consider attack the best defense
Fast Casting - Is it useful?
Heighten Magic - I prefer Channeling

Third tier:
Armor Proficiency - Seems too limited

Well, what do you advice?
I'm considering Harmony + Channeling + Clarity or Meditation.