@Sinker: The templates are good guidelines, but they're not hard and fast rules, or the only types of characters you can play--in fact, the Scion "template" is a lot like the Pure Mortal "template" in the sense that it isn't a template at all so much as a very broad category if disparate character types that happen to have a basis in common.
I'd say his supernatural good luck
is a power, similar to "Guide My Hand"'s trapping of being able to be in the right place at the right time without having to spend a fate point for it.
And that is what I have a problem with. Because I came up with a cool story for this character, I get penalized. If I described this character as merely a lucky mortal (or simply never explained where the luck comes from) I would have been capable of all of the same things but with no penalty. It's discouraging creativity in preference of RAW over intent and I hate it when my GM or players stick to the RAW even when it is impractical or even (in this case) harmful.
The difference I see is that a Lucky Pure Mortal would have the +2 refresh bonus, but would have to spend one of those fate points every time he wants an advantage from it. A Luck Scion would have a -0 refresh power, and be able to take advantage of the ability without spending that fate point (once a scene, or whatever). If they use that power more than once between refreshes (and if it's the basis of the character, it's a safe bet they will), then they're already breaking even. More than that, and you're coming out ahead. And if you and the mortal both have no fate points, then you've got the advantage.
@Tedronai: It's not worth 2 refresh; it's worth 0.
The +2 refresh is not the standard. That 2 refresh is a
bonus for not having any supernatural-ness at all. It's not something that any player is entitled to. It's something that a player is given for deliberately avoiding the the most potent abilities available in the game.
It doesn't matter if the power you've taken is only going to be useful once a scene. It doesn't matter if the one power you've taken is
actively detrimental to you, as is the case with Cassandra's Tears. It doesn't matter if the power didn't already exist in the rulebook.
If you have a supernatural ability, you are not a Pure Mortal, and don't get that 2 refresh bonus.