I haven't really submitted my maps from Halo 4 to the community yet because my maps are either 8 vs 8 size competitive maps or 4 vs 4 size maps that hit on what I like to call a "Shadow Barrier". I which, too many stuctured elements put into one map will break the limit of which structures, scenery, etc. can cast shadows in the map. You might already know that but, keep that in mind.
Now lets get back to my Halo 4 File Share. My favorite competitive map forged by me is called "Overwhelm". It's a 4 vs 4 size competitive that takes place at a closely guarded UNSC facility. It's a very competitive and coolest looking 4 vs 4 map in my File Share. Another 4 vs 4 size competitive map called "Reflex" is again, a UNSC facility, this time in a forest like terrain. It'll be fun to play Snipers on it because all the trees inside the facility walls. The two maps I just talked about are recommended for Red vs Blue Team Slayer or Objective based competitions. Of coarse, I have alot more competitive maps aswell.
I also have a forge art called "UNSC-Predator". It's my version of the Covenant Scarab found in the Halo trilogy. But the UNSC-Predator is a UNSC machine/vehicle (Can't really drive it.) about 1.5 to 2X larger than its competition walking on four legs. Be sure to read the discriptions of the content from my File Share before playing/viewing to see how they work or what you should do on them.
It's also important to see my Xbox LIVE Profile's bio for new maps, game types, etc. that have been released or is coming soon. And to see which maps that have been updated recently. You (and others) can read my bio when you are signed into Xbox LIVE on your console.