Tim the Diviner's page

The menacing style is more interesting but perhaps more risky since potentially dangerous opponents like undead, constructs, oozes, paladins, plants, and vermin are immune to intimidation.

Another way to get free intimidation checks is Cornugon Smash. It does the same thing as enforcer but requires power attack instead of nonlethal damage. If you want to use these intimidation rules, and you're making lots of attacks, can also tack on Cruelty.

Being vulnerable to attack regardless of position and intervening obstacles is also disconcerting for your opponents.
Flesheater Barbarian is ghoulish and can give you a fly speed.
Horizon Walker 3 (Astral Dominance) + Dimensional Assault less you do teleporting charge attacks.

Lesser Spirit Totem is somewhat annoying for the other players to manage, so if you want to go down that route you could try watching each character that accepts your song and handle the preconditions and attack rolls yourself.

I personally enjoy Beast Totem and Greater Beast Totem.

Everything seems shipshape, so I've only a few comments to make.

Ability Scores:
I personally prefer to maximize the casting stats of full arcane casters. Having high spell DCs is important.
Don't be afraid of dumping Strength. If you aren't lugging around weapons and armor it should be easy to avoid carrying capacity limits and spells like mage armor and mirror images should make you an unappetizing target for shadows.

Spells:
Phantom Steed (3rd) - If you want to use full-round actions to cast metamagic spells I would reccomend using a mount, and at high levels this becomes one of the best.

Items:
Circlet of Persuation - It can be worn in addition to a headband. It may grant a +3 on concentration checks depending on table variation.
Wand of Mage Armor - Its not as good as casting mage armor yourself, but if you have prestige points to burn its probably worth the extra spell known, especially at low levels.

Feats:
Noble Scion (War) - Something to be aware of, especially if you want to start with higher Charisma.

If you're willing to spend a feat you could get Golden Legion's Stayed Blade to reduce opponents to -1 HP. It's similar to dealing nonlethal damage.

:( Doesn't work, since it's a resistance bonus. If it were a circumstance bonus, or a sacred bonus, or a competence bonus, I would definitely consider. Although ~10k is a bit high to consider in addition to your normal cloak...

I would recommend a Lucky Horseshoe. It gives a +1 Luck bonus to all saves and a 1/day +4 luck bonus on one save for scary situations. Bonus points if you have Fate's favored.

Your first problem is that you didn't read channel energy ability. "but only to heal creatures with the cold subtype or to command them" means that you cannot channel energy offensively.

That is correct. I don't think that this Druid would able to perform a Channel Smite attack.

Guided Hand requires you to have the Channel Smite feat, but I don't think it requires you to be able to use it.

A druid doesn't gain proficiency with their deity's favored weapon. So unless you intend to dip, in which case there's not a lot of reason to go with an Arctic Druid, you're kinda hosed...

Pharasma's favored weapon is Dagger. Druids are proficient with daggers.

In PFS, can my Level 1 Druid with the Arctic Domain choose Channel Smite as their 1st level feat?

The Arctic Domain's Call Cold ability has a clause to prevent Druids from using similar feats, but I have no intention of actually using Channel Smite. I just need it to qualify for Guided Hand.

Here is the relevant text:

Arctic Domain

Call Cold (Su): You can channel energy (as a cleric of your druid level) a number of times per day equal to 3 + your Charisma modifier, but only to heal creatures with the cold subtype or to command them (similar to using the Command Undead feat against undead). You can take other feats that add to this ability, such as Extra Channel and Improved Channel, but not feats that alter this ability, such as Elemental Channel and Alignment Channel. The DC to save against this ability is equal to 10 + 1/2 your druid level + your Charisma modifier.

Channel Smite

Prerequisites: Channel energy class feature.

Benefit: Before you make a melee attack roll, you can choose to spend one use of your channel energy ability as a swift action. If you channel positive energy and you hit an undead creature, that creature takes an amount of additional damage equal to the damage dealt by your channel positive energy ability. If you channel negative energy and you hit a living creature, that creature takes an amount of additional damage equal to the damage dealt by your channel negative energy ability. Your target can make a Will save, as normal, to halve this additional damage. If your attack misses, the channel energy ability is still expended with no effect.

Guided Hand

Prerequisites: Channel energy class feature, Channel Smite, proficiency with your deity’s favored weapon.

Benefit: With your deity’s favored weapon, you can use your Wisdom modifier instead of your Strength or Dexterity modifier on attack rolls.