Just as a heads up, I think I'll include a second idea in this page. So, first of all, this whole first thought hinges on the knowledge of Chivalry of a Failed Knight, which is a light novel/anime. It also requires some knowledge of the Nasuverse but I think a vast majority of people on this site know Fate/Stay.
Now, I'll give a brief generalization of Failed Knight. Basically, there are people with supernatural abilities called "Blazers" who manifest weapons from their souls called "Devices". These superhumans go to school to become Knights. Now, this school has a ranking system from F to A, F being bad and A being geniuses. The main character, Kurogane Ikki, is an F-Class Knight, due to his poor talent in magic. I highly recommend reading the light novels or watching the anime for a better understanding, but there is only one season of the anime so your best bet is the novel.
So, with that pretty basic understanding, I think either Unlimited Blade Works or the Gates of Babylon would be fairly powerful in this world, especially if coupled with magecraft. Unlike the last idea, I won't be giving any thoughts on how the mc gets in this world, because I think only reincarnation would work for this one. You know your standard, "God accidentally killed me but is making up for it by giving me wishes." kind of deal. I realize that both UBW and GoB are really overkill, but it's the power-trip kind of fan-fic.
For plotlines, there's the obvious "I'm the main character now, so I get the women" but you could also try something else, like merging a couple other anime worlds like akikan40 does. (Note: No disrespect, I love their hard-working spirit) Again, like I said in the last chapter, I'm not giving all the answers.
Now, onto the other idea, I was thinking of an inFAMOUS fan-fic. This one I think would have a much better plot if the character is not someone from our world, but an actual resident of the inFAMOUS world, with no idea of future events. I don't know what kind of powers they should have, but I have a few ideas.
First idea is metal, specifically iron. Even more specific, iron sand. I mean, it's perfect for offense and defense. Creating swords and shields, shifting into iron sand to dodge, coating your body in a thick layer for armor, the possibilities are endless. With this as his power set, he's basically Magneto, at least to an extent. Maybe one of the ways he regains power is by siphoning out the iron in a human, or leeching iron out of steel. Plus if you choose to make him a villain or anti-hero, Cole is his worst enemy since his electricity powers will easily damage him. (This is sounding more like a game than a novel, but I'll roll with it)
I had thought about water being a possibility but I'm not sure it would go over well in universe. Water is the most abundant resource on Earth after all. Maybe you restrict it in some way, making overuse dangerous. I guess electricity would work on the character the same way it does on the iron sand.
My third idea is phosphorus and its deadly flames. This power is definitely for a villain, if you've ever played Spec-Ops: The Line, you know why. Just imagine wiping out an entire city with a blanket of white phosphorus. I don't know specifically what phosphorus abilities would entail aside from projectiles and bombs, but You can think of something.
I haven't really refreshed myself on what exactly happens in inFAMOUS, so this power may already be there. Plants, I think would be very versatile, if you use them like Poison Ivy, or think like a Mokuton practitioner. I mean if paper can be used why not plants. There are a few other powers I thought of, but I'll leave it at four.