Replacing the intake manifold

[Headnsouth]

I've got it all tore down and I'm ready to order parts. I've looked at Dorman gasket sets and like the fact that they come with replacement bolts but I feel better using Felpro.
http://www.autozone.com/autozone/par..._259704_19388_

Should I replace any bolts/seals or anything else while I've got it opened up?
Definitely replacing the thermostat.

What about the seals on the valve cover bolts? Fuel injector o rings?

Spark plugs/wires have 20K on them.