What a nice bar! Maybe you should add a pendant light or two--something to ramp up the style of the area, make people look at the bar, want to go to the bar and so on!
I'm thinking of something a little modern and metallic to match the area.
Like this: http://www.lightsonline.com/mini-pendants/fredrick-ramond-globe-2-light-mini-pendant-in-polished-chrome-finish-fr38510pcm/
Or this: http://www.lightsonline.com/mini-pendants/savoy-house-mont-la-ville-mini-pendant/
But really, there are so many pendants that the possibilities are endless.

I would consider going with a warm paint color under the countertop that is close to or in the same color family as the sectional. Perhaps something like Benjamin Moore's Simple Pleasures. I would add pendants in a warm color, perhaps orange since I see that elsewhere in the room, and art with some of the warm colors on the wall at the back of the bar. I would also add in black barstools.

Some really cool bar stools would look great with your new bar.

Here is a Houzz article on picking a great bar stool. Some are pricey...the one below is reasonably priced.
https://www.houzz.com/magazine/how-to-pick-the-perfect-bar-stool-stsetivw-vs~750682

Consider open shelves notched around the column / plumbing chase so it visually disappears - thick black shelves that float will tie in best. You'll want a large square canvas with bright tones on the wall behind / where the cabinet doors open. This should set a color accent for your room - other than the two wood tones on the windows and column, (complimentary ochre based tones) you are all neutral - so perhaps add some red-orange and ochre in this art piece. Something graphic and tied to your own interests/hobbies will be strongest.

I do think painting the base in contrast is a good idea. With revere pewter, you don't want to go too blue-gray like some of your test swatches. Try bm fieldstone http://www.benjaminmoore.com/en-us/paint-color/fieldstone or antique pewter - consider a venetian plaster type finish on the bar instead of a plain paint - mix joint compound with a mechanical mixer with your paint to thicken then smooth trowel it on. It variegates the color a bit, and gives it the look of a plaster wall.

Finally, good bar stools are not cheap, so don't buy just anything. Pier one has some value priced leatherette parsons stools that have clean lines. Simple is best here since it is front and center as you walk in.

I would def put something under the bar considering people sit there and tend to hit it with their shoes etc..... seen bricks under there before and it looks great. Or some stone. accent color Firecracker red... just saying...!!! keeping it Bar style.. good luck cant wait to see the end result