Regarding could have, should have, I think it's only legit to criticize a decision based on the info available at the time but so long as that's obeyed one can criticize a decision.
Take the infamous Tate selection, IMO that was only defensible if one believes that >4yrs of Tate would have a better impact on the team than 5yrs of Wallace. I wasn't following the draft at that point so I don't have an opinion of them as prospects but I know a bit about injuries, and I know that losing 1yr out of 5 and the fact that one is never 'quite the same' after those kinds of injuries really makes me wonder about the decision.