You are not really answering the questions very well; one sentence answers just don't tell us a damn thing.

IF the car does this only after sitting a long (several hours) time, then:
Get in the car.
Turn the key all the way to on, but just don't go so far as "START", let it sit for 10 seconds.
THEN turn to START.

If it starts on the first try, then we have low fuel pressure due to a pressure bleed or leak while the car is sitting.

If it does it even after you just drove the car, then I'd wonder about a dirty MAF - and it COULD be that you bought an oddball CPS and the PTCM is not getting reliable data on crank position. Did you buy a BOSCH CPS or some oddball part somewhere? If it was not an original BOSCH, then order one now.

The rough idle implies the MAF or perhaps bad/dirty injectors. The plugs should be fine to at least 90,000 or more miles. My last car didn't get plugs and wires until 102,000 and ONLY because I was getting misfire and O2 codes - they all went away with plugs and wires. And, the car started and idled fine with the old plugs.