If it's a PC it sure could have console emulators. Personally, I think the other console emulators on an arcade are overrated. I built mine with them, but they are all disabled. With few exceptions, console games don't feel great with an arcade stick. If you want something to emulate console games, I'd recommend spending the extra $50 and pickup a raspberry pi and controllers. I also went though and deleted 75% of the arcade roms. I feel like these guys with 4000+ arcade games have a lot of bad games. My build is currently sitting just under 500 games.
I'd also say with controls, sometimes less is more. Most people first starting out want everything. It just becomes overly complex, especially for guests. Do you really need a spinner, trackball, wheel, flight stick, etc. Yes, they are fun every now and then, but for the most part a good 2-player, 6-button layout is going to be all you need.
My number one suggestion with buying them, is to not overpay. These things homemade builds are a dime a dozen. In most cases they are an empty cabinet ($50), cheap pc or raspberry pi ($50), input device ($50), monitor ($50+), and controls ($50+). There are exceptions, but for the most part that's the basics. When looking what to pay, I'd look at how well put together it is. If it's some guy slapping it together it's worth it's value in parts. If it's well made then perhaps it's worth it to you to not have to do the work yourself.