Since you want to get more eyes on your names, I suggest you list them everywhere you can, i.e. on Afternic, Sedo, Dan, Uniregistry, Epik, Daaz, Domain Agents, Biix.com.
Unless you have some special strategy and know what you’re doing, you will want to always list at Afternic & Sedo for maximum exposure. These can bring sales even when you park the domain elsewhere.
Then choose a platform to host (landers) your domains — DAN, Epik, Efty, own website and so on… Plenty to choose from. Afternic and Sedo can also be used for this purpose.
I've personally never listed at more than two services at one time. But I'm happy to move them around from time to time. 99 times out of a 100 it's the lander (home sales page) that's going to see the sale
Just remember to keep your listings consistent across the Boards if your using fixed pricing. Probably better to list as "Make Offer" if your using multiple platforms.
I’m still trying to figure it out. Check namebio to see if certain places sell certain TLDs better. Mostly Dan, but DaaZ for .in, Sedo maybe for more Euro domains. Just keep trying until something clicks. I’m still new (months) so maybe check back in a year. So far, I’ve only sold at GD auctions. Still in the red.