Right now Jason Bulmahn is trying to find out a new way to deal with Amazing Initiative. Why Because to get an extra turn every single round is a really powerful ability. So here I would like to begin the discussion around the Agile template.
Agile (MR1) is the template who has the lowest MR, but in my opinion it has the greatest bonuses. You double the speed of the creature, get more AC, get Evasion, and you act twice per turn...
Let's compare it to the Arcane/Divine and the Invincible/Savage templates.
The first two gives the creatures some spells. It's good right, but the creature will probably never have the time to really benefit from those, unless it has time to buff itself before combat. SR is really good, Aura of grace is nice.
The two last gain DR and energy resistance.
Now let's get into a combat situation.
An Agile creature will act twice in a single round, that means it can move a lot (speed is doubled), and/or attack a lot, making it a quite nasty creature. Yes its hps does not increase a lot, but it can become a quite challenging foe.
Now if you take the Invincible or Savage Template. There are quite a few way to go around the resist energy or the DR/epic. Clustered shot being one of them.
Yes it's a nice boon to have a DR, but will 10 less damage per attack will really mean a lot for a group of adventurer of level 10+?
Not from my experiences. Yes it can give it maybe one more turn of play, but the Agile creature will probably get more from his template than a savage/invincible creature (who has a higher MR)
In the end, it does seems to me that the Agile Template is the most interesting (and powerful) tool here, even if it's MR is the lowest. It can transform a creature into a Solo encounter, which is honestly quite awesome.
Arcane seems to be the 2nd best, because of it's SR which can be hard to deal with.
Savage can be quite nasty, but I do not feel it is as dangereous as Arcane or Agile.
Divine is quite interesting if you want a creature to assist the others in a combat.
Invincible all alone doesn't seem that good. I do understand the intent, but the fact that it can deflect one attack per round doesn't seem that important when there is a group of adventurer against it. The fact that the savage template gets the same resist and DR than it kind of make his name a bit sad.
My general opinion is... those are awesome. It's a quick and easy to use, I can easily build quick mythic creatures with those, and the possibility of stacking some of these templates together might make some very interesting encounters.
Now what do you think about these templates?
Should the Invincible template be given a little boost?(I sure think so, maybe increasing it's DR by 5)
Is the MR of Agile too low? (I'm a bit confused there, because it is a very powerful template, but increasing it's MR, might make the creature too weak in battle. A single level or tier for the PCs can be a huge boost of power)