Success mostly depends on weapons and piloting. There are many good gun combos.
Kerosene, phoenix claw, and hydrogen is the standard pilot loadout for all ships except mobula. Mobulas don't need phoenix claw and substitute for drogue chute (often used on spire too). Mobulas have slow turn acceleration so they start turning slow, but have good turn speed and high turn momentum. Getting used to turning is necessary so practice in practice first. Mobulas are a floating gun platform and usually have long range guns, so sharp turns are mainly for close range defense.
Stamina helps turning and is great for moving up and down- what mobula is best at. Mobula has excellent vertical mobility, but this means they fall fast when balloon is broken. This can be good for escaping, but hitting ground is death. I always bring drogue chute and hydrogen. Drogue chute also reduces impact damage by 25% just like impact bumpers. Note that hydro lasts 5 seconds so don't use it longer than an instant. Tap on off and hold up. Use stamina!!
Moving up or down is great for dodging and tanking. Use plenty of kerosene and never be afraid to use it. Burn burn burn and judge repairs, tell your crew what to do because they can't see well. The most important pilot skill is using tools and the most important captain skill is communication.
If your balloon is about to break, turn drogue on slightly before and hydro immediately when it's rebuilt if necessary. Mobulas are light and maneuverable (albeit slow) and can easily dodge other ships. It's my favorite ship to fly.
Mobulas usually have a set of long range guns and a short range option if necessary. Merc double artemis is common for long range, and carronade flame for close.
My standard mobula is merc top, flak gat left, mine artemis right. Hull engi (left) brings lesmok spanner mallet extinguisher and uses lesmok for long range on flak and gat (and regular when in range). Balloon engi brings burst spanner mallet chem with burst for artemis. The gunner brings charged for merc, heatsink for light flak, and charged heatsink lochnagar for mine launcher.
I bring an extinguisher because the pilot can touch the top gun by jumping. The hull has extinguisher and balloon has chem. There's enough time to chem balloon during the artemis reload (6.5 seconds) and is good because balloons are vulnerable to fire.
Crew start on merc flak art for long range and change position based on the enemy and position. They may be on merc gat art, flak gat art, or mine gat art. The gunner brings ammo for all 3 guns, charged is the best for merc, heatsink is great on flak, and charged heatsink lochnagar allows shooting mines at 3 ranges. If there is time, I load incendiary into mine to start with.
I use 3 other mobulas. One is the same but with a spanner mallet buff engi on merc and flare instead of mine launcher, another has hades with spanner mallet buff lesmok with the flak and artemis positions swapped, and the last uses a mine launcher with a gunner and similar loadout to the hades mob. The hades and mine have burst for the left artemis gat, and burst or heatsink for the bottom right light flak. Top right has a gat on hades loadout and a hades on the mine loadout. The purpose of having the spanner mallet buff engi on the hades and merc is to maximize damage and repairs.
Experiment and have fun. Change your key bindings because you can't fly with the standard keys. Ideally you need to be able to use all movement, throttle, number, and voice keys simultaneously with no overlap. I use the mouse buttons for throttle and shift/control for voice. My 1234 is Alt mouse3 mouse4 Q, stamina is middle mouse. C is map, X is Tab, and F is captain spot.