A theory of fantasy football

I'm about to put together my fantasy team for this season, and this will be the first time I've really given much thought to it, so I'm still pretty new and uninformed about how it works. I've come up with what I think is the optimal way to build a team, but if anyone reads this who actually knows what works, I'd appreciate it if you'd leave some better advice in the comments. I'm laying this out to see if anyone knows of a better approach, or a serious problem with this one:

Since there's not really any interaction between the different players on your team, it makes sense to focus your attention on the positions that typically result in the most points. Not sure what the best order is here, but it seems likely to be the case that this reflects the major skill positions (QB, WR, RB, CB, etc). So it should be the case that there's an ordering of positions that makes the most sense - i.e., you want to draft a QB first, then a RB, then a WR, whatever.

There are probably also an extremely small number of players who, irrespective of their actual positions, tend to rack up a lot of points, so if there's an opportunity to get one, they should be gotten.

From there, since FF is about making predictions, you should focus on 1) individual player skill; 2) fitness of a player to their team (a fantastic WR isn't going to get you much if he has Rex Grossman throwing to him, sadly); 3) strength of opposition (but I'd expect that this is so hard to predict that it should be the last thing to be taken into account.)

A good starting place would also seem to be something like nfl.com/rankings, which appears to just straight-up rank players by their FF scores (I presume based on last season). Is this site to be trusted? It's the official NFL site, so...I wonder.