Question about buying Carter BBD for my 318 (unless I should look at something else)

The engine was bought in '87 as a remanufactured crate engine from a chrysler dealership when I was restoring the car (my dad's car). It is an LA engine, the original was a polysphere (Canadian car, which explains why there was a 318 in a C body to begin with). I only put 10k miles on the car after that, and the car has been in storage for the past 25 years. I took it out for the first time last year for a couple weeks, it's out again and I wasn't liking how rough it idled. I think I might have partially solved that by replacing the coil (secondary resistance was measuring 24k ohms when it should be 11k, I had a few old / original coils to compare with and swap).

I've put in new points, condensor, rotor and balast resistor, new plugs (RN14YC). It did have a combination of N and RN 12YC before it was stored. Plug wires are silicone, 500 ohms per foot (so not crazy-high resistance wire nor straight zero-ohm wires either) but they are 20+ years old.

Compression tests, even when done cold, are 150 - 160 PSI after 4 cranks.

Plugs are black / sooty. Best idle vacuum I can get is 17 inches with a 1 inch bounce at 500 rpm. Vacuum goes to 20, maybe 22 when RPM is 1000 - 1400 (engine runs very smoothly at those higher rpm's).

Very very little play in throttle shaft. Choke pull-off works great. The carb air-horn gasket (the gasket between the main carb body and the top air-horn casting) seems to seep a little bit of gasoline when running. I'm wondering if there's too much fuel in the bowl. I've adjusted the idle mixture, I can turn 1 screw completely in and idle is very rough but it does keep running.

I read about the need to clean these various low-speed idle passages and such, the idea of just replacing the carb with a brand new one is growing on me (I didn't know they were so available and so cheap).

I don't think I'll get any further by changing more ignition parts. I did recently buy a new NGK 53420 (RC-CRX010) wire set which also has 500 ohm/ft and a new blue streak dist cap with brass contacts but I want to hold those back for a few years until the car really needs them.

I don't mind running lean if it clears the plugs and I get better milage. Should I buy the newer-style BBD carb with all the ports? Do I just plug the extra ports?