Just like in real estate, the key things to consider are “location, location, location”.
Obvious things to watch for are backgrounds. I've seen cake photos that were spoiled by backgrounds such as fire extinguishers, basketball hoops, bulletin boards with kids construction paper crafts all over it, kitchen pass thru windows (which were open so you could see the kitchen clutter!), and yes, even men's room doors!
Do not put the cake table next to the DJ and do not allow the DJ’s speakers to be directed toward the cake. I’ve heard too many stories from cake designers all over the country about wedding cakes that collapsed due to the vibrations from a loud speaker (especially those with lots of bass pulsing out of it!). Many cakes aren’t put together like Lego’s, with nice snap-together parts. They are sitting on dowel supports or plastic pillars, and a loud constant vibration from a speaker IS enough to cause the cake to vibrate its way right onto the floor.
You wouldn’t think I’d have to explain this one, but if you’re planning an outdoor wedding, it’s pretty accepted that putting the cake in direct sunlight is a bad idea. Bad. Very bad. Oh let’s call it what it is … it’s downright stupid. A cake that’s covered in icing made from butter and someone thinks, “Oh let’s sit it over here, where the 85 degree sun can beat down on it for hours and hours! Yeah …. THAT’S a good idea!” (Shoot me now. Just shoot me now.)
Listen, if you ARE one of these folks who thinks it’s a good idea to put a wedding cake outside in the direct sun, let me give you another good idea. Do NOT call your cake maker and ask for a refund when your cake icing melts and runs down the side of the cake. You won’t get one. I swear, you won’t.
Oh .. and indoor weddings have the same rule. Do not put the cake table next to a big picture window where the sun is beating in thru the window, directly on the cake. Do not place the cake table over a big heat vent in the floor, or under an overhead heat duct. Not only is the heat a bad thing, but odds are good there is dust and other air particles settling on your cake as it blows out of the vent/duct.
Once a cake is set up, it really REALLY shouldn't be moved. Some cake designs can be moved, but play it safe and assume yours can't. So don't set up a reception with the idea of "oh, we'll put the cake here for now and move it later." Stacked cakes sometimes can be moved......cakes set up with pillars really shouldn't be moved.
In my never-so-humble opinion, the wedding cake is the centerpiece of your reception, so display it front and center! Don’t hide it in a corner somewhere! For 30 years, I’ve been working wedding receptions and I can tell you that people don’t line up to take photo’s of the table linens or the centerpieces or the banner behind the Head Table, but they DO line up to take a photo of the cake. As they enter the reception room, they are looking for the cake. So put it in a place of honor.