The current options:
Ugh...the thought of running that group out for another 162 games is downright depressing. Nishi was over matched all year and the reports that he has trouble hitting harder throwers seems to be true. His fielding was to be honest brutal and I have no faith in him as a SS. Plouffe is more suited to a utility role in my opinion as his inconsistent throwing arm and defense rule him out as a full time player up the middle though his offensive potential profiles well there. Alexi is also more suited to a utility role and has never been able to stay healthy for an entire season anyway.
So onto what is/may be available to upgrade the SS position:
Free Agent Options:
Clint Barmes (33)
I think he is the best option available, assuming Houston does not resign him. He just finished his first full season at SS after palying 2B and some SS in Colorado. Fangraphs rated his defense at +7.9 UZR this past season and I believe he is capable of sustaining that level for at least a couple of more seasons. As for offensively he has a career triple slash line of .252/.302/.401 which is nothing special but when you consider the average AL SS hit .258/.314/.370 his career line would be slighlty above average. I would compare Barmes to Plouffe but with above average defense. If he is available I would offer him a two year deal worth 13m and would consider adding a club option for another 7 million if that would get him to sign.
Nick Punto (34)
Who missed Little Nicky Punto?? We all know what he is about and I am sure Gardy is panting at the thought of bringing his battle his tail offness back to the club. I would not be opposed to it if no other options are available and it was a one year deal around 1m.
Jose Reyes (29)
I am not interested in him for the money and years he would require.
Jimmy Rollins (33)
Marco Scutaro (36) - I do not think Boston will cut him loose but I would interested in adding Scutaro and his strong career walk rate to the club as well but he is 3 years older then Barmes and his defense is not nearly as good. Though a one year deal at 4 or 5m would probably get me to bite but he would probably be able to command more then that if he got to the open market.
Jed Lowrie (27) Boston-
If Boston where to retain Scutaro they may be willing to listen on Lowrie. He triple slash line in almost identical to Barmes but he is considerably worse on defense posting a -4.1 UZR in only 88 games. Frankly, I would rather take my chances with Plouffe turning it around on defense as I think he is capable of matching Lowries output offensively and they are similarly bad on D.
What would it take to get Lowrie?
Since he is still fairly young and cheap he might cost to much anyways for the Twins to bother but since Boston needs starting pitching in a bad way maybe they would be interested in straight up Slowey for Lowerie swap but most likely not. I would not move any of our top 10 prospects for him.
Macier Isturez (31)
I doubt the Angels would deal him but he has shown in the past that he is capable of playing short and his good eye and OBP skills would be an ideal fit in the bottom of the order or even in the two hole.
What would it take to get Isturez?
I think it would take a descent prospect to get him put not a top 10 type maybe one of our corner OF types like Angel Morales would interest them with the aging combo of Hunter and Wells.