Q: Loss of power

my dodge ram has power but i feel like it is not performing like a 5.9 does. I replaced plug wires, plugs, oil, oil filter. So basically a tune up but from what it was before, it has way more power but when i drive i can tell something is still worn out. I thinking i need to replace cap and rotor but not for sure or maybe a sensor. My research led all to catalytic converter since it had misfires for a long time until i got my plugs in the mail, so I'm guessing that all the carbon built up in the catalytic converter. i ran seafoam i the oil and gas tank until the gas tank ran out and then i did the tune up. I feel like my injectors still junk in them and bought a injector cleaner but wait for tank to run down so i can mix with new gas. what your guys idea that it might be because i feel like something is getting worn down but just cant get my head around it. I am also gonna clean throttle body and get a new ignition coil. the transmission is good maintenance already.

My car has 184000 miles.
My car has an automatic transmission.