I think you're very strong in starting pitching, that's a great advantage you have. The lack of closer is something that is one of the easiest things to fix in fantasy baseball
I'd drop Marte and get Koch since Koch gets the first shot at closing. Might as well pick up some saves while it's out there. But drop him the first sign you see him giving up 3+ times of 3 ER innings because the sox will be replacing him with Takatsu or Marte in a second.
I wouldn't get Joe Mauer since I'm really not on the same boat as everybody else that Joe Mauer is the next big thing. Though I still think you can replace Toby with somebody better (e.g. Robby Hammock)
I have Biddle on my roster cuz he's the inked closer so far... He's unlikely to implode right off the bat when the season starts so might as well get some saves from him.
I don't like Teixiera, where are you gonna put him? Your 1B and 3B are better than him. Raul Mondesi is probably on even par with Teixiera in the OF...so no, you're in pretty good shape as is.
Dude, drop Cameron and get Kazuo Matsui right after you read this. I can't comprehend how in the world your league didn't draft him. He has a huge upside and is very likely, IMO, better than Angel this year.