Help with cold start after car sits for about six hours

Hi,
Im having trouble with my 2006 Chrysler Sebring Convertible (1300000 miles). The car is having trouble starting (it cranks every time) after the car sits for about six hours. It takes about 4 - 5 cranks to start in the morning, but after that the car runs and starts smoothly for the rest of the day. I have no codes currently but a P0430 code for catalyst under inefficiency on bank 2 comes and goes, but i believe the cat is unrelated. However the engine runs lean and may be the cause of the cat and the cold start issues now, I'm not sure. I just replaced the spark plugs and I saw oil in cylinder one on the plug, so that is also a concern. I can only think of a hand full of other things it could be and after buying the fuel pump thinking that would solve the issue I kinda want to be able to test and fix, but any advice wold be appreciated thanks.

Things it is not:
-Battery (had it removed and tested at auto zone, 100% good, only one year old)
-Starter (had it removed and tested at auto zone, 100% good, pretty old)
-Alternator ( good replaced with battery)
-Fuel pump/filter/pressure regulator (just replaced)
-Spark plugs (just replaced)
-O2 sensor (just replaced the bank two pre-cat one, because of P0430 code and rumors of rough start issues)

-visually inspected all injectors and they appear to be seated and clean
-visually inspected coil packs all appear to be fine (except for the one i broke and replaced :banghead:)

So just to recap, you've had an on-and-off code related to your catalyst, your engine is running lean, and you're finding oil on a spark plug. I think the combination of these problems may be the roots of the main starting difficulty problem. These things all need to be addressed. Oil fouled spark plugs won't spark properly. An engine running lean will have difficulty starting and it will be down on power. An inefficiency code related to your catalytic converter may mean that it's restricted which would cause too much backpressue.
Look I hate to be the bearer of bad news, but I've seen so many problems with Chrysler Sebrings it's not even funny anymore. These issues are definitely repairable, and once you sort it out, your car will run like a champ... until something else goes wrong and wind up doing a lot of this::banghead:

^ Thanks for the advice I guess, but buying a new car is not an option at this time. Also the car runs fine except for the initial start up like i was explaining. I'm getting the car looked at next weekend and im doing some things to tests in the meantime. Right now im cleaning up and maybe replacing the thermostat temp sensor. If there is any advice on how to fix or test things for my situation please let me know.