Personally I would get the OP's w/ult. reason; break a spoke fix it at any shop, toast a rim you have hubs that will last forever just rebuild, probably going to be lighter, should have a nicer ride depend on laceing. if building you can make very light with diff spoke/nipple combos.
Cosmos; easy out of box sale for shop guy? heavy, not as servicable ie: spokes, You trash em your probably not gonna rebuild em.
Make sure who ever bilds them knows what they are doing and FYI I am not a big fan of OP's but given your choice its a no brainer for me. Also if you kill em in a few years rebuild with somthing better.
Pedals; Thats tough, float can aggravate knee conditions as well. what are you currently using? sometimes it better to get your knee in the correct position and leave it. I think trial and error is your best course of action, and remember there is no holygrail of pedals. Most do the same things, just in diff. ways. Congrats on your new rig and best of luck
Jeff