First things first.
Welcome to the crew!
Now about the size;
I would say if there were never going to be an addition number of people you could have gotten a bit smaller size. But if you were cooking ribs you will like having the extra room for side dishes and such.
jm2cw
As for the charcoal, in my experience I only use it to light my offset RF smokers. The main fuel is sticks, a couple of fist sized splints every 1.5 hours and so on.