I think it all depends on how the draft unfolds for you also. If you get to the 5th rd and there is a rb there that shouldn't be there then you take the rb and fill out the roster in the next few rd's. I don't like to go into drafts saying I'm going to go rb, rb, wr, wr, or have any set formula to how I will draft my team, I have my rankings and try to stick with them. Oh the one thing I do in my drafts is not draft a kicker until the last round. Other than that good luck.
Agreed with dblj. I don't go into the draft saying,"Oh, I'm going RB/RB/WR/WR/RB/WR". I normally just take the best player who has the most value IMO. But normally, I always end up with my RB3 and WR3, maybe even a RB4 or WR4 within the first 7 rounds If McNabb is sitting their at late 6th or early 7th, I'll snatch him before I start working on my WR depth, but this year I really like Schaub late in the draft, so I'm not to worried about getting a QB this year with guys like Palmer falling to the 10th.
I'm not saying have a set draft order... but just a general of how many of a certain position you like to have.
For instance, if you go "best available" as you call it- what's the criteria for "best"? It's subjective, yes, but what's the standard you're measuring against to get "best"? How do you judge whether RB X is more valuable than QB X?
Let me flip the question- what if "best available" happens to be a grouping of Running Backs every round? It's now round 5 and you have a stable of 4 RBs on your roster... do you still take a RB? Nope. Why? Because you only want a certain number of them by round 7.
I had 4 RBs by rd 7 in my first draft this year. I tend to draft leaning towards a best player available mentality. I think you have to have a general strategy in place, but each draft is different. I like to have my starters and a quality backup RB by rd 7.