My theory was that anything cooling related was a 'must have'. Head gaskets and other general engine damage can be caused by overheating. Things like injector cleaning can be done at a later time and are more in the 'nice to have' category, especially if it was running OK before.
Sounds like you have the right list of things to do. A lot of people (myself included) have had the injectors serviced like you mentioned. I had them done at RC Engineering, and they came back clean and with a nice report. Head bolts if you use OEM, or ARP head studs if you want to go that...