i would definitely do the rear foglamp and dynamat together since you will need to remove the trunk liner anyway. i'd suggest installing a rearview camera as well while you're at it.
as for the others i suppose you can do the rear diffuser and exhaust at the same time.
im not sure if the latest evo-r one fits correctly or not. i heard they improved it from their original version but was still not at the level of the fujimura.