Cams for 318's

Too many variables to just throw out a recommendation but I'd suggest you get the head casting numbers and run a compression test. Then decide what the rest of the combo will be. The cam needs to match your rear gear and converter . No good to have a cam that starts to pull at 3500 and tops out at 6k with 2.97 rear gears. You will never use the power. Don't over cam!!! Weight of vehicle intended use? Highway usage? 4.56s are a fun gear....
I agree with most of what you said, except the 4.56 gears will cause the 318 to scream at just cruising speeds. 3.55's with a mild stall converter would give the best bang for the buck along with a good flowing dual exhaust system and recurve the distributor.