Sweeeeet! And I see you have a stool there waiting for me.
Nice job on the bar. I can easily picture friends hangin' out and enjoying some home made stout.
About smoothing out the brick, here's what I would do. The crumbling areas need to be cleaned up real well, and completely free from any lose dust. A corn broom is good for that, and some water to prevent creating a dust cloud. If you can blast it with the garden hose, all the better.
Then I would get some wood fiber plaster, a plastic mortar trough to mix it in, a mortar hoe to mix it with, a 14" hawk to hold it with while using a 12" or 14" steel trowel to apply it, which I would also get.
Note the rounded corners on the hoe. I did that with my 4-1/4" angle grinder to accomodate the rounded corners inside the plastic trough. Pretty smart, eh?
Then I'd mix about half the bag of plaster with the recommended amount of water, and let it steep for a few minutes while I wet down the brick. That way it doesn't suck the water out of the plaster faster than you can apply it, and allows it more setting time.
I'd use the steel trowel to mash the mortar into the brick and deep into the joints so it gets a good bond, and I'd apply it thick enough to cover the brick by about 1/4" thick. I'd do this to about a 3' square area at a time, trying not to re-trowel what I've already applied, so as not to pull it away from the brick. If the wall starts getting dry I'd wet it again. Believe me, that brick is going to soak up a lot of water.
Then I'd clean my tools and admire my work.
Note, there is a good chance that over the years some of it is going to crack and come loose. No big deal, just chip it away and patch it with the same method.