Alright, this can work, it's good that you base it heavily on yourself since you should always write what you know, but you cant rely on that forever (though many big successful authors do that.) Also, don't rely too much on gore, but instead on the psychology behind the gore. That's the big issue with the written word. It's very very good at delving into the minds of the characters and the mental effect of events such as extreme violence, but it's not very good at really shocking someone visually unless the psychology is there, (It's why the Call of Chuthlu RPG is seen as so horrific because the creatures are about insanity and suffering of that kind).
That said, some successful authors do make their name on mindless violence in serious tales with no psychology, and i'm not a successful author, so take my advice at that value.
First person writing is very hard, you cant describe anything at all that the person cannot see at the point when it is described. For example, if a character slept on a hard floor and woke up with an imprint in their face, you cannot mention that imprint unless there is a mirror nearby.
The date thing is perfectly fine. I find it a bit gimmicky, but it's a mainstream technique so people must obviously like it.
oh and always protect your stories. Most people wouldnt steal it since they have their own ideas, but obviously there are those who will without a second thought about it.
I mean I recentle read a webcomic that stole jokes from Monkey Island, The Flea and all kinds of other stuff. That said, everyone steals from everyone else somehow. As the saying goes, "a good author copies, a great author steals"
If my advise sounds confusing, that's because it is. There are no rules in writing. You can do what you want as long as it's entertaining. I mean that's the whole point of it, right?