Luis Valbuena is now a placeholder for newly-acquired Mike Olt who's in AAA (and then Kris Bryant, but that's further down the road/he could be playing LF). Valbuena as a third basemen is 15th in wOBA (.322) at a minimum of 250 PA. If he were to move to 2B, he would be tied for 12th in wOBA with the Pirates' Neil Walker. Darwin Barney is 21st among second basemen with a .261 wOBA, so you can see the potential upgrade in production (Barney is .282 wOBA vs LHP 99RC+ / Valbuena is .273wOBA vs LHP 65 RC+). With Barney's excellent defensive ability and splits against left handed pitching, you could justify keeping him or trading him as he is entering his first year of arbitration eligibility next year (as is Valbuena).
Mike Olt has been compared to Dan Uggla with a better glove and supposedly has Evan Longoria's body type. There has also been a comparison to Mark Reynolds. Uggla's .334 wOBA is 10th among 2B even with his 30%+ strike out rate. If he was at 3B, he'd be 13th, just behind Cincy's Todd Frazier. Assuming his power shows up in the big leagues, Olt could very well slot in our lineup 4th/5th/6th. The good part about his Iowa stint is that the same instruction given to correct Anthony Rizzo's swing will be there for him to utilize. He's a patient/power guy that will take his walks, something this front office enjoys. I think the highest ceiling from Olt's first full season next year is something along the lines of what Kyle Seager is doing in Seattle.
If we can extend Ryan Sweeney and end up keeping Nate Schierholtz, this team could surprise fans in 2014. I think re-signing Dioner Navarro (after we trade him or not) or signing someone comparable like Brayan Pena is a good idea since the available, free agent upgrades like Brian McCann and Jarrod Saltalamacchia will cost $9M-$17M+ AAV on the open market. Signing Omar Infante to play 2B, sending Luis Valbuena to the OF would be an effective way to 1) not have a platoon at 2B and 2) allow a game plan for the trading of Barney, Schierholtz, and David DeJesus to acquire decent prospects. I believe Valbuena could play corner OF spots adequately as well.
OBP - wOBA - 2014 Lineup
[.500], [.547] 1. Lake LF
[.342], [.373] 2. Sweeney (L) CF
[.337], [.367] 3. Schierholtz (L) RF
[.???], [.???] 4. Olt 3B
[.331], [.335] 5. Rizzo (L) 1B
[.340], [.322] 6. Valbuena (L) 2B / [.355], [.373] C Navarro (S)
[.330], [.301] 7. Castillo C / [.283], [.282] 2B Barney
[.286], [.282] 8. Castro
SP Wood (L)
SP Rusin (L)
SU Russell (L)