Well, taste is up to you but here's what I usually do.
1 flash on camera with a diffuser (fong, flip-it, stofen), in a "bounce" mode. I usually work in manual, unless the situation allows for TTL (but most of the time it doesn't.)
1 flash high in a corner, triggered by a PW. Use the PC-sync on your camera for the transmitter, and usually a straight bracket (
General Brand Straight Flash Bracket VA322 - B&H Photo Video) to hold it. Usually manual, 1/8 or 1/16 power, depends on the room.
This setup creates a main light (on camera flash) and a bit of fill or kicker depending on where I'm situated in the room. I keep my shutter lower to allow for a bit of ambient, around f/2.8, and ISO800-1250. To mix it up, I'll move so my remote flash is 90º to me and the on-camera acts as a fill.

Here the kicker is directly behind the groom and my on camera flash creates the light illuminating most of the couple. The 2.8 allows for a nice DOF and a high ISO allows the ambient to bleed in (coincidentally it also allows me to keep the power of my flashes low for faster recycle time).
Now the situation is flipped, the corner-remote flash is the main and the on camera is a bit of fill