Hi All,

After consulting with you all, I ended up getting a used 2012 Specialized Secteur Elite Compact (Tiagra components) few days back. I ended up buying used, so that I use the savings to buy accessories. I am basically going to use the bike to commute to work (4 miles total, no need for a rack as I only carry a MAcbook air in my bookbag) and then do 25-50 miles over the weekend initially. Here's my preliminary list:

Already have - Helment, Cheap 3M Glasses, Leg Strap for Jeans, Front and Back LED lights, Saddle Bag, Multi-puporse tool kit, Bottle Holder and Bottle

To buy:
a) Repair Kit
b) Additional bike shorts and shirts

Question
a) Spare Tube - My front tire is 25mm and back is 28mm (conti gatorskin). Not sure why different sizes but do I need separate tubes or can I grab just one? If so which size?
b) Pedals - Never used clipped pedals but leaning towards dual platform pedals as it will be convenient. I've read about Shimano PD-T420, PD-A530. Any suggestions on going dual or clipless only (replace during weekend). If dual, which one?
c) Shoes - I am a 10/10.5 US size (wide) and recommendations for a basic one? I would prefer something light.

Anything else I am missing from above? Again not looking to splurge but just get a hang of things intiially.

AR