Sounds awesome! I like "vertical" space in PvP a lot... places you can climb, stairs and ramps...
same, one map that comes to mind is the last ground map, from the last Romulan mission. <3
You could keep the Orbital Strike mechanic in, make it a pvp-objective.
Take the Orbital Strike Nodes and place them on top of each of 3 Buildings.
Either faction can initiate an Orbital Strike from any of the 3 buildings, against either of the other 2 buildings. Which would totally destroy the target building (and its corresponding Orbital Strike node).
Once you initiate an Orbital Strike, it takes so long until it actually activates-during that time, players from the opposing faction can cancel it (but only from the node where it was initiated).
More like a King of the Hill with 3 Hills lol but you could pull it off any number of different ways.