I dont' know if any of them are an upgrade over Belt at this point. If I had to rank them, I'd rank them as such:
1) Alvarez shouldn't even be an option. He's just not good and if you don't catch him on a hot week he's virtually worthless.
2) Davis is intriguing, but he could be in the same boat as Belt........vying for playing time. They guy is batting 7th too, shame really. I love him, but he needs moved up in the order to put up gaudy numbers.
3) Lind, I'd wait and see. Not sure how he'll respond long term from his demotion.
4) LaRoche is intriguing. He's getting PT and typically heats up in the second half. Could be on a 30/100 season, but his average is going to bring your teams down.
5) Aoki is intriguing too. Decent average, will get your runs and SB's.
I don't know where your teams deficiencies are, but the only two I'd consider right now is LaRoche and Aoki. viewtopic.php?f=26&t=449830