Okay so update, if you are wondering why it took so long, that is because I suddenly caught myself picking things off my list I did not really want to use because I thought it would make people less angry at me than everything else. I very nearly quit the game when I realized this. Instead I took several days off and reevaluated. So here it is.
Surt gives a fire barrier that keeps shit out and burns it if it comes in anyway; As a trade off Minato can't fight or leave the barrier and once it goes down it starts it's three day recharge timer.
Skadi gives ice control that can't make new ice, gets weaker the closer he gets to the ocean, and is useless against anything more durable or better at dodging than the local canon fodder.
Odin gives Sleipnir Motorcycle. Because Fucking Sleipnir Motorcycle.
Oh yeah I was going to give a summary of why I am adding all this stuff to the personas.
It is a trade off I made with myself for using the base stats and move lists instead of my fully customized personas that I grinded up to max level and loaded up with incense cards.
It was also an excuse to use a bit of my immensely meager writing ability to come up with something interesting that fits with either the theme or the legend/myth/story that the persona comes from.
So there you go, have at it; rip out my throat, tear out my liver, cut out my heart; I have little hope left of mercy, well I have little hope left period.
--EDIT--
Please ignore that last part, I have just gotten past the worst two weeks of my life and there is more to come. Please forgive my foolishness.