I like Austin and Bailey best in dynasty.
There are reports that Britt looks like he has regained some of his burst, if so, I wouldn't rule out production. If he returns to form (it does seem unlikely, but possible), he could easily be their top WR in 2014, if he avoids injury (another question mark), though he isn't signed beyond this year, and it is unclear what STL would pay to retain him if he blows up.
It is also unclear what to make of the Quick reports. He has reportedly always looked good in practice, but had trouble putting it together in games. Should we think this time will be different? I would only say I don't think he had this level of buzz before. Again, probably not a high percentage play, but if the light went on, he has the physical/athletic ability to have some upside.
Bailey was already taking snaps from Pettis by the end of the season, and appeared to have passed him on the depth chart (but complicating depth chart inferences, his emergence also coincided with Austin missing the last three games). Pettis just isn't explosive and is more of a possession WR.
If Givens were to extend the good things he did as a rookie in 2012 (rather than regress even further than he did in a 2013 soph slump season), he could start.
Just about every STL skill position player (except for Mason) is in a crossroad season. It's almost like everyone could do well if given the opportunity, or everyone could disappoint. Probably a few will bubble up to the top, and a few won't.
I'm not sure but doubt their base set will be a wide open 3 WR attack. They will use 2 TEs at times, a FB at others. If the season were to start today, in 3 WR sets, I think it would be Britt and Givens on the outside and Austin in the slot. In 2 WR sets, I don't think Austin will necessarily be off the field, so there could be some kind of rotation. His speed can stress defenses on the outside in different ways than from the inside. Austin isn't big, so they may put him on some kind of pitch count equivalent for weekly game plans. But that could depend on how well he does and holds up, what the other WRs do.
Once Bailey returns, if Britt or Givens suffer an injury or stumble, I think he is further along than Quick and would be next man up. Baily may be talented enough that if the door is cracked open to a starting job, IMO he could break it down. He reminds me of Derrick Mason.
* Of course, it is possible that none of them lead the team in receiving, like last year, when Jared Cook did.