I think that we are fine this year with Amendola, Thompkins and Edelman. Edelman is certainly is better than last year's version of Branch.
The bonus we have is in Dobson and Boyce. We should be able to get some production from at least one of them. And yes, one can step is our #3 when Edelman is injured and likely produce at least as much as Branch did last year.
So, my expectation is to have the four newbies for the playoff run and playoffs (and to have Blount returning punts).
I don't think comparing to last year, or any other year, is an effective approach.
Saying someone should be better than that years weak link does little for me.
The fact, IMO, is that we aren't putting different guys into the same role, we are altering the offense to what we have.
I think you will see:
Amendola being less effective at what Welker did, but adding facets that Welker was not strong in (such as breaking long run after catch, and being more effective down the field (more often).
I'm not sold that Thompkins is the #2, but more that 2/3/4 will be split among all of the other receivers, and their varied skills.
All of them better do more than Branch did.
I see a much more versatile group.
Edelman will catch screen passes. Boyce seems like a young Branch in strengths and weaknesses. Dobson has the skillset to do everything we want a WR to do.
Its just a matter of who develops at what pace.
I don't think we will get to the end of this season and say it was less than it could have been because of the WR position.