Touring - Giant OCR 3 what should I do to convert to Touring?

I have a modified Giant OCR 3. It has Shimano WH-R550 bladed wheeels, 700x 23 tires, FSA Gossamer External bearing 172.5 cranks, 105 triple front derailleur, 10 speed Ultegra rear derailleur, 9 speed SRAM cassette and chain and Tiagra 9 speed shifters. I have a good rear rack and Cannondale panniers but would like to hear what other mods you guys (gals) would do for light 2-3 day touring? Wardie

For 2 or 3 days of touring, I don't think you'd need any major changes. Especially if you're staying in hotels.

The only thing I'd probably do is use wider tires -- 700c x 28 at a minimum.

You might also want to temporarily raise your handlebars -- either even with the saddle, or up by about 1". This will give you a more relaxed ride and a better view.

Crank length and number of gears isn't that important. What matters is if your gearing is low enough for you to climb hills with a bunch of stuff on the rack. If you can do that, you're pretty much set.

I agree absolutely with 700 x 28 tires. I keep those on my road bike permanently---good all-purpose size.

You will need full fenders if rain is a possibility. Check to see if fenders will fit between the tire and brakes.

I had full mountain gears put on my road bike and love 'em. Those would come in handy for touring.

Check to make sure you have enough heel clearance for your panniers.

And you will need more than 1 water bottle. Any place to put 'em?

I agree absolutely with 700 x 28 tires. I keep those on my road bike permanently---good all-purpose size.

edit

I've read this many times but why can't regular 23 mm tires suffice?

I understand:
Added weight of touring gear on 23mm tires--> pinch flats
Bigger tires --> more comfort

What else am I missing?

I ride up to 100 miles/day on 23 mm tires without problems.
My weight fluctuates between 215-235 lbs so the tires are pumped to about 120 psi - 135 psi... should I seriously be considering changing my tires to a 25 or 28 just for some light touring?