Obnoxious thundercaller questions

[ohako]

So, in V: BoL, the thundercaller archetype has some fun supernatural bardic performances that duplicate the effects of spells.

a) these performances are listed as supernatural, not spell-like abilities, but there's some funny wording there. Can I, or can I not, use feats like Spell Penetration or Spell Focus (evocation) to boost their power?
b) every other bardic performance uses the standard style saving throw (ex: dirge of doom, 10 + 1/2 level + Cha mod), but again, funny wording. Do I, or do I not, use the standard style or the spell style when using these performances? (Because frankly, a damage-scaling sound burst is pretty boss, but an AoE stun with a scaling saving throw is even more boss, yeah?)

Here's another question: If I have two different abilities that both grant half-rank bonuses on a skill (say, bound to the land and heart of wilderness), do the half-rank bonuses stack up to a whole rank? In other words, at 7th level, is my Survival bonus +7 or +6?

I'm pretty sure I know this answer to this one: if a thundercaller performs (wind) with a totem spear, his/her versatile performance (wind) would cancel and supersede the bonus to Handle Animal from bound to the land, correct?

EDIT: duh, you couldn't use metamagic to boost something that doesn't use spell slots, outside of obvious 3.5 cheese

EDIT: ooh, I got another one!

Let's say you start up a thunder call performance. During your turn, when does the sound burst hit? At the beginning of the round, or the end? Here's why: Let's say you're doing your performance, waving your totem spear around to call the thunder, and you've got nothing better to do with your standard action than to put on a Dazzling Display with said waving-around-totem-spear. Can you attempt to demoralize your sound burst targets before it hits, or would you give your...demoralizees...an extra round to scurry away?

[ohako]

Hmm, lemme try to clean these up,

a) does a thundercaller using thunder call force a saving throw of 10 + 1/2 the thundercaller's level + Cha modifier (normal for an Su ability) or 10 + 2 (sound burst's spell level) + Cha modifier (spell style)?
b) If the saving throw is spell style, can a thundercaller use the feat Spell Focus (evocation) to boost the DC?
c) possibly a common alternate race trait for Shoanti might be heart of the wilderness, which in part grants a bonus of 1/2 to Survival checks. The thundercaller ability bound to the land also in part grants a bonus of 1/2 level to Survival. At an odd-numbered level, do these half-bonuses combine to make a full +1?
d) A thunder call performance, like all bardic performances, can be maintained with a free action once started. I would like to demoralize my targets with a Dazzling Display before the sound burst effect goes off for the round. Do I have to maintain the bardic performance at the start of my turn, or can I wait until after my standard action?

[TheRonin]

These are good questions, so I shall bump this.

[Cheapy]

Let's see...

a) Thunder call isn't sound burst, and it seems like it only has the same aspects of it that are listed. Range, area, saving throw. The saving throw would be 10 + 1/2 level + Cha mod.
b) It's SU, so Spell Focus Evocation would not work on it. I don't think it'd even work if it was an SLA.
c) I believe they are separate pools, so no.
d) Theoretically you could choose whenever to use a free action to continue the performance. But I am fairly certain that the author intended for this ability to be standard action only and that you could not maintain the ability. There are a fair number of bardic abilities like this. Take note of Call Lightning and Call Lightning Storm. They both have special text about how they work when maintained. Thunder Call also has the "spend a round of performance" language that non-maintainable abilities tend to have.