You want a load out that works or one that is just fun to fly? Because yeah the Pyra poop deck usually gets relegated to utility weapon (still really important, especially in bigger matches where a flare gun is very important), and the main deck is usually a backup, but if you are willing to offer up effectiveness on the altar of fun there are a few interesting things to try.
1) Artemis / Artemis / Artemis / Artemis
Before you take this make sure you play around in the blast yard so you know where to put things, and you will need moonshine (and probably drogue chute) to ensure you can make the ship stay nice and still. All four guns can have arc at one time giving ranged killing power and disable ability. Main engi takes the poop deck, you grab the main deck gun. You want something like heatsink for the added turning because you will need to run back and forth, everyone else wants burst or lesmok or something similar. You will also need someone else to break the armour for you. Make sure you have crew members target different components so they don't waste shots. When I've used it it sort of works, there were a couple of occasions when all four guns on the pyra were firing at the same time and lots of components broke repeatedly. It is hard to fly, the arcs hardly overlap and it is a chunk of work. The ship still functions okay in close combat, you can use the front Artemis to take out an enemies engines and then either bolt it or if they cant face you just grind them down. The lack of ability to break armour, the small arc overlap, the need for constant communication and good targeting make this a suboptimal build, and a good crew is going to just sneak up on you and make you miserable, but when it works it is fun.
2) Carro / Flamer / Banshee / ?
Lots of people have pointed this out, but a Banshee at 3 is great. Especially for the Carro / Flamer Pyra. Rams can be unreliable (especially when I'm driving) and when you have someone pinned and burning a way to speed up death is nice, and the Banshee does the job without you needing to turn too far or lose arc on the front guns. I actually think this is better than a flamer. If the enemy is good, they have chem spray and all that emergency gun has done is help them with their marshmallow roasting project. If the crew is bad then them being behind you and to the left isn't an emergency, it's why you brought Pheonix Claw. If I'm worried about needing my side guns for that kind of situation I bring a carro and aim for balloon or engines and hit hydrogen / kerosene.
3) Banshee / Gat / Banshee / ?
Top Banshee and Gat can be swapped but it slightly reduces arc overlap. This is one to take when you notice your enemy doesn't have adequate fire fighting capabilities but darn you are just bored of flamers. Also nice to bring with a less experienced crew, they can all fire wildly and effectiveness only drops a bit. Experienced crew is going to eat you for breakfast with proper fire fighting and a flak or mortar. It aint good, but it is viable and pretty fun to use. Some novice crews probably use this more effectively than the meta.
4) Carro / Carro /Carro / ?
The enemy squid really starting to get on your nerves? Sure you are going to struggle against good crews, but at least that squid will stop moving, then stop flying, then being attached to itself. Make sure you know the arcs and that each person knows what they should be shooting, you want one on balloon, one on engines and one on guns for most ships. If it is a squid you want one on engines, one on engines and seriously stop moving you pain in the backside!
Out of these the only one I would say 'works' in the sense of being comparable in power to one of the more meta loads is (2) (and really it is a meta load, carro / flamer, just adapted to use the side gun). Having rapid fire explosive damage your main engi can use without you having to take main guns off the target is very useful. Everything else, try for the lolz. If you get a weak pick up crew still trying to learn the difference between a mallet and a buff hammer (3) probably wont do you any harm.