I would say that, in the event of teams occurring again...
Reimu + Yukari
The Homing Type
Reimu, unfocused, fires homing shots. Yukari fires needles, but in a manner of EoSD/PCB (ie - not the strongest at long range,)
Reimu and Yukari have always been together. So... Yeah. Reimu's bomb would be orbs as always, Yukari's would involve trains.
Marisa + Byakuren
The Forward Focus Type
Marisa, unfocused, would fire trees again, in a slight spread. At long range, it's the strongest unfocused. Byakuren fires Star Maelstrom lasers that start going out but converge at the closest enemy
directly in front. Plus piercing. Definitely the strongest at range.
They're both magicians, and in MarisaB's scenario - the only confirmed canon - Byakuren offers Marisa a reward, though that might be just returning home. Besides, since Marisa's partner isn't a stage 3 boss, she isn't worthless. Marisa bombs using the Master Spark, Byakuren goes Superhuman.
Ichirin + Murasa
The Spread Type
Ichirin shoots bullets in a pattern resembling her midboss nonspell in a 90~ degree angle. Murasa fires 3 anchors at a very slow rate of fire that deal relatively massive damage. They're still spread out with about 30~ degrees between them, but hitting a boss with all three is the strongest DPS in the game. With just one, though, it's on par with Reimu. Oh, and they explode for splash damage.
I can't really think of any pairing for a UFO team, though Shou and Nazrin make sense. Ichirin bombs using Unzan BROFISTS and Murasa uses Dipper Creeping Closer for little base damage but a long time to shotgun.
Sanae + Nue
The Remilia/MarisaC Type
Sanae fires stars in a slight spread that still deals respectable damage at any range. Nue uses UFOs to position anywhere, but they have infinite range like Remilia but slightly less damage than Mari/Bya.
Sanae B in UFO pretty much kidnaps Nue to take a picture, but who knows what happens after that. Sanae is trying to become dependent, so her bomb doesn't involve her gods. Nue fires orbs everywhere that change into random bullets that then fly into enemies.
Haha, I still would prefer having a
player character and a support.