Ours is an umbrella. There is a "grid" below the umbrella though into which the umbrella attaches via a post screw. Ours is exclusively for washing hands in a powder room. It does flow a bit slowly but I believe that is due to a plumbing grade issue that I choose not to repair right now as it will involve opening the wall.

I didn't really consider the drain issue with our bathroom we just did. We went with a square undermount sink with center drain and overflow in the front. But, I do have to tell you that because of the distance front the drain to where our faucet is installed in the concrete countertop, that because there's too much distance, the drain will hardly come up at all (it's not a "pop-up" drain). So, we either have to be creative and try to make something so the drain pull that is hidden behind the faucet will work to pull-up the drain, or purchase a pop-up drain and install it. Here's the faucet we got. Here is a link that might be useful: Loki faucet

It depends on the type of faucet you ordered, more so since you have a vessel sink. If you bought a copper finished faucet that has a lift handle for the drain, then that company will normally offer a drain tailpiece in the same finish. That setup may or may not work, depending on how you install the vessel sink. that pop-up would look like this: Should you want a drain tailpiece with a pop up that is not connected to the faucet, ie, it's operated indepently, again, those should be available. You can either get a "press and pop" drain, or a manual "lift and twist" pop-up like this: ...or if you don;t want to hold water in the bowl at all, you can get a plain old drain tailpiece like this: First thing I'd do? Find out from the manufacturer of the faucet that you purchased what types of drain tailpieces and pop-up assemblies that they offer. They would give you the best bet of matching the finish of the drain to the finish on the faucet. Mongo

Wouldn't it be hugely simpler just to get an undermount sink? They do make them in all kinds of glass/ceramic if that's why you're considering this. How do you plan to support it, how will you keep the counter from pressing on it, etc?