This would work, and accomplish everything without totally ruining the experience:
Upon starting the game and clicking on Online Arenas / Open Melee, you get plopped in a tower with full radar and no comms. You pick the field you want, and once in that tower, you get normal radar and comms. The first tower would include a popup with basic info on how to get started. At the end of your sortie, you can go back to the first tower if you want and find more action.
That accomplishes the goal of showing new people that there's action in the map, without degenerating into what happened this weekend.