Well I think we can all sympathize with that limitation.
Solidarity
Fair enough.
And just fer the halibut I went searching for what big budget rappers are putting out for videos.
http://www.billboard.com/charts/rap-song
Time for more of my own homework.

Feel free to swipe creative ideas!
EDIT:
Alright, those McLemore vids were just way too expensive to even steal ideas from.

The one that looked closest to what we usually see here is 'Gas Pedal'.
Looks like about four or five primary locations, different camera positions and multiple approaches at each location.
If you had the opportunity to reshoot using ONLY that one massive LED screen as a location you could:
Singer + camera 90° to background
Singer + camera 45° left of background
Singer + camera 45° right of background
Singer 90° to background + camera 45° left of background
Singer 90° to background + camera 45° right of background
Singer facing background + camera paralell to background
Singer facing background + camera paralell to background
Singer facing background + camera 90° to background
Singer facing background + camera 45° left of background
Singer facing background + camera 45° right of background
Long shots
Mid shots
Close ups
Bring in a couple of relevant-to-song props or characters or other group members (could be the producer or promoter for all I care. Girlfriends and groupies are great.)
Get shots of them.
Have some mild interaction between them.
Next time... In the car. In the hallway. In the stairwell. In the parking deck or parking lot. At the house. In a hotel room. Heaven forbid - in a proper performance venue.
For me, pretty consistently, I like seeing big groups of people involved.
If the client is any good surely they have some buds, some peeps, some family that would wanna help or get involved in promoting their career.
I like that Don't Drop That Thun Thun!' video the most.
'Thrift Shop' was pretty fun, too.