Personally, and while these are builds I seek to try in the future, I have had tremendous success with a spire on Desert Scrap. I sit on the point and when some bugger comes rolling around the cylindrical walls we pepper them with gatling fire, a hwacha, rotate on the reload to hit them with a top-right carousel or flak, and finally I have a flare or flame-thrower on the bottom for tormenting the crews that didn't bring extinguishers.
I love the turn speed it has and often found myself jumping off the helm to mount a gun, usually resulting in our definite capture of the point and game... however...
I was a fairly low level when I began my experimentation with different ships and, around this time, the gat/flak combo became the go-to guns for any low-level pilot to utilize for a quick and painless severance of the Spire. It was a great method, mind you, but I feel kind of scared going back to the spire without fighting in Scrap and without a teammate to help guide me along.
Regardless of all this, I think I'm going to summon my special crew and try out a brawl and sniper build to see which ones I like better... perhaps get some more flight time with this ship and find out if it ends up working or not. I like being versatile, and I hate seeing my Spire sitting useless and alone as I scroll past it to a more favorable ship.
If you guys find anything that is grade-a, please post here, I would love to know. If not I'll surely comes across you in game when the Spire makes its comeback and dominates everyone in its gritty reboot sequel or something.