I would like to see EPIXDVN - Epix Drive-In. Time Warner used to have this, it was part of a the EPIX group of pay channels. They had it on for free one Saturday, before I came to DirecTV, and it was fun.
Also I would like to see OAN - One America News Network. This is a new up-and-coming channel that is seeing some growth on cable. I have read that DirecTV wants to hear from people to gauge interest before they add it to their lineup. Many just don't know about it yet. If you are interested and want to see OAN added, call DirecTV and tell them you are interested. (I see it is already on ATT UVerse, so this may be in the works or somewhere down the line already)