Our WRs were awful in the NFC championship game...or were they? Yes, Crabtree had 3 drops, etc., but doesn't it start with Alex Smith? A great QB can make a decent WR look great. Eddie Royal had 91 receptions as a rookie when he had Jay Cutler throwing to him (playing opposite Brandon Marshall also helped a lot), but managed 115 in the past 3 seasons without him. Austin Collie and Brandon Stokley looked like studs at times with Peyton Manning throwing to them.
The Niners have (ready for this?), in my opinion, one the best solid WR corps in the league. Notice that I didn't simply say "best". No, they are far from great, but as a group they are solid. Many teams have better WRs, but taken as a whole (and as individuals) the 49er WRs are solid and not many teams have several solid WRs. So, what am I getting at? Peyton Manning is what I'm getting at. If the 49ers signed a mid-tier WR to bolster the group such as Eddie Royal, Robert Meachem, Reggie Wayne (hmmm, interesting), or Laurent Robinson, and landed Manning, he would have a host of good (not great) targets. Along with Manning, Vernon Davis, Crabtree, and perhaps another WR could all be Pro Bowlers (let me just say that for all of Kyle Williams' horrible flaws as a kick returner, I think he has vast potential as a slot reciever).
Manning is such an elite QB he can make any of these good receivers, great. Luring Manning to San Francsico would not be easy as there are multiple teams expected to aggressively pursue him. Also, the team is committed to Alex Smith, and I'm not ignoring that. For Harbaugh & Company to turn their backs on him after his vastly improved season last year and after Harbaugh has gushed and gushed over him would not only be a huge shock, it would also be pretty messed up; but that is business in sports. The only way I see Smith going elsewhere is if he and the team are miles apart on contract negotiations and/or they could get Manning for roughly what Smith is asking.
With Manning and one of the above mentioned FA receivers signed (preferably Wayne), and with Morgan and Ginn re-signed, the team can focus on filling other needs early in the draft (CB, G, etc.) and look for a WR or KR later on. Now, this is a pretty big "if" right now, but if Manning could get us 27-30 TDs, 4,000+ yards, and keep INTs in the 10-14 range, for the next 3 years (all the while mentoring Kaepernick), we could be talking about at least 1 Super Bowl ring.
On offense, take care of our own free agents, sign Manning and another solid WR. I'd rather pay big bucks to an elite, hall of fame QB (albeit one coming off a pretty serious injury) like Manning who will instantly make all of the Niners offensive skill players much better than break the bank on a guy like Mike Wallace, for example, who is great but would not have the type of impact that Manning can have.
It remains to be seen how much (or how little) Manning's neck issue affects his throwing and his success (and durability) depend on the 49ers O-line keeping him upright. There is no way it's worth pursuing him if he is going to be sacked 30-40 times. However, the teams needs to think about it. I wasn't at all on the Manning bandwagon, but I'm starting to warm to the idea. I would feel bad if the team turned it's back on Alex Smith after the strides he has made, but I wouldn't feel so bad if he asks for way too much money. We have some solid receivers, Davis, and Gore and Hunter who would all benefit immensely from a successful Peyton Manning. Although we could use an upgrade at WR, we could get a potentially massive upgrade at QB which would impact the entire offense.
With our WRs and Manning, we could surely put up 20+ points per game; we know the defense can hold teams (way) under 20, and our special teams are the league's best. Whatdya think?