Yes, the 2016 nomination battles are on, and reporting on them is a great idea.
That said: let's not get ahead of ourselves. It's too early to game out Iowa, much less the events after that. It's too early to declare a candidate (say, Marco Rubio) has already lost his chance. It's not too early to say how policy positions are affecting the contest right now -- but it's still too early, for most issue areas, to have a real sense of how things play out in 2015 among party actors, and certainly too early in most cases to know how they play out among voters in 2016.
On the other hand, it's worth knowing which candidates are sparking intense interest among party actors, as well as which candidates are running into hostility from party actors (and yes, that might be the same candidate from different groups of party actors).
OK, so that's fairly tricky. And what makes it harder is that we really don't have a good roadmap. Yes, elite endorsements seem to matter, or at least they are good indicators of what's going on...but we really don't have any systematic way to predict whether it will be Cruz or Rubio or Kasich or whoever, or to explain why party actors go for one but not the other.
The upshot of that, in my view, should be caution. Gather and report as much information as we can, but be cautious about how to interpret it. Remember how few iterations of this process we've had, and even then it's hard to generalize across them because both the system and the parties have changed over time.
Again: reporting on what the candidates and party actors are actually doing is great. Some speculation based on that is fine. But try to remember that there's still a long time remaining, and the issue landscape changes all the time, and so do candidate apparent fortunes. Caution, everyone