The 49ers are bringing in almost every free agent receiver for a visit besides Mike Wallace: Brandon Lloyd, Chaz Schilens and Mario Manningham for sure. Maybe others. Lloyd has had the best career, while the latter two are a little younger and have cooler names (especially because Manningham’s middle name is Cashmere).

If the 49ers sign one of those receivers, their top three at the position (Michael Crabtree, Randy Moss and ???) wouldn’t exactly be the best trio in the NFL, but it’d be a much better group than the receiving corps they had last season.

Adam Snyder signed with the Arizona Cardinals today, which should be just fine for the Niners and their fans. Snyder was game, and he was better than Chilo “I epitomize Mike Singletary’s coaching career better than anyone” Rachal, but he was a lower-tier starting NFL guard. Still, San Francisco needs to go into next season with more at the position than Daniel Kilgore and hope.

Niners Nation brought up the possibility of the 49ers signing the recently released Robert Gallery or Leonard Davis, who didn’t play a down last season. While those options make some sense, the 49ers probably go into 2012 just as weak at right guard with Kilgore, Gallery and/or Davis as they were in 2011. As a team that allowed a lot of sacks last season and features a balanced attack, a hole in the offensive line means no holes for the running backs. And that just won’t do.

So what should the Niners do? Here’s an idea.

Trade up for a guard.

Now that the 49ers have the same 11 starters key contributors on a defense that developed into an elite unit last season, it’s almost ludicrous to spend any draft picks higher than the sixth round on a defensive player. Okay, maybe they could use a cornerback. Or someone to back up the front seven in case of another DUI or two (hey, it’s a concern on this team). But the 49ers can probably add the depth they need on defense via cheaper or undrafted free agents.

The point is the early stages of the 49ers’ draft will focus on the offensive side.

San Francisco also has their best team in years, a squad that’s literally a player or two away from Super Bowl contention. And they only need reinforcements because they can’t count on the same turnover ratio they enjoyed last season, and their 2012 schedule looks to be incredibly difficult.

Two guards are slated to go in the first round before the 49ers pick at No. 30: David DeCastro (Stanford) and Cordy Glenn (Georgia). DeCastro’s one of the better guards to enter the draft in years, and many mocks have him slated to come off the board before highly-touted former teammate Jonathan Martin (tackle). Glenn was a tackle in college and may remain one in the NFL, but there’s a good chance the 345-pounder will be moved to guard — at least initially.

The 49ers could still get a guy like Marvin Jones, Juron Criner or Mohamed Sanu in the second round to boost their receiving depth (unless they trade their second rounder to move up in the first round).

Would the 49ers give up a pretty valuable draft pick (or picks) to move up 10 spots or so, when they seem very hesitant to give up significant money and their current No. 1 for Mike Wallace? Probably not, but crazier things have happened (like the Niners signing Randy Moss).

Just food for thought as we wait for Alex Smith to sign the dotted line.