The captain's return to the deck has Glim pausing in his efforts to calm and sooth the refugees aboard. At her words he looks at the assembled civilians and asks her "Is there room belowdecks for the folks? We don't want them at more risk if we can avoid it."

I'm guessing it hasn't been a long enough period of calm to count as a short rest for us?

He looks to his new companions and adds, "I don't think I can do much to the ship itself, but I may be able to fog the minds of the crew, and I'm sure I can help man one of the ballistae."

(What is the range? Anoushka can shoot Eldritch Blasts to 240’ and ignore anything but full cover…)

”T’chaki!” she curses loudly. “To the forecastle! Go, go, no, not you!” She uses Rusalka to pop teleport past any particularly intractable knots of townspeople to the forecastle.

Wreji will coral the people down below. "for your safety, best best be  under deck. We'll keep you out of harms reach travelers!" 

He rushes to the nearest Ballista, teleporting if he needs to make up any distance to get there in time. "Another fight yeah? Things keep getting more and more interesting."

Nip swoops down to the deck.  "It would be better for me to fire on them from above but if I need to work a ballista, I will.  Call if you need me." 

Without waiting for an answer, Nip will fly above the ship and ready his bow.  As soon as he can see someone within 600 feet, he will fire twice.  He has the sharpshooter feat

Attacking at long range doesn't impose disadvantage on your ranged weapon attack rolls and your ranged weapon attacks ignore half cover and three-quarters cover. 

Attack 1 - Attack: 18 Damage: 8

Attack 2 - Attack: 26 Damage: 14

If either hit, the swarm will do their thing and feast for 6 piercing damage

Pim moves to the back of the Galleon, carefully checking his bowstring as he does.  He ignores the refugees scrambling for cover, focused instead on calculating closing distances, assessing the approaching craft for weaknesses and looking to do what he can to buy themselves some time.

Perception (looking for vulnerable crew, obvious weak points, general sizing up of the enemy) 22

• Yes, you can count the time as a short rest - go ahead and make any needed adjustments =)
• Yes, there is plenty of room below decks for the townsfolk to hide.
• Starting distance is 1000' and it will take approx 1 minute for the star moth to be in range for its mangonel (800'). At this point the Moondancer will come about and the ships will close at max speed. This will give you the time to move people below deck and take up your positions.
• I will put the range between ships each round. 
• It takes 3 people to operate 1 ballista. One person loads, one person turns the wheels to aim it left/right and up/down, and one person operates the firing pin. You can have townspeople help load and pull the firing pin. Ballista range is 120'/480' and it does 3d10 piercing. Whoever is aiming can make the rolls using your ranged weapon to hit modifier.

Looks like Glim and Wreji will man the 2 ballistae, Pim and Nip will use their own ranged weapons, and Anoushka readies a spell. Sound right?

Round 1 (800') - Sure enough, the star moth is faster than the Moondancer, and as it draws closer it sends a large chunk of stone hurtling through space at you! You watch in morbid fascination as the tiny speck grows larger and larger... As planned, once the star moth fires, your ship comes about and races towards the pirates! You each start calculating closing speeds and ranges, preparing for your shots.
(Attack vs AC15: 16 Damage if hit: 29)

Round 1 (con't): Moondancer shudders as the chunk of asteroid impacts the aft weapons deck where the mangonel was. Wood splinters and the screams of frightened townsfolk can be heard from below. 

Round 2 (715') - You can just make out four exposed figures operating the mangonel at the top of the star moth - and they quickly reload and send another round your way! (Attack vs AC15: 20 Damage if hit: 30)

Round 3 (630') - (I don't think anyone can hit at this range, right?) The barrage continues, but Moondancer maintains course and speed to intercept! (Attack vs AC15: 17 Damage if hit: 16)

Round 4 (545') - (Anyone besides Nip with a longbow?) Nip sends two wooden shafts soaring through the vacuum towards the star moth, both hitting one of the creatures manning the mangonel! It drops to the deck, disrupting the loading of the weapon and buying the Moondancer a momentary reprieve.

Round 5 (460') - (Ballistae in range w/ disadvantage.)

While they herd the townsfolk below, Glim tries to persuade a few of them to help man the pair of ballistae, so that he and Wreji can fire them.

Persuasion: 28

If successful, he'll try to work with them to get them loaded and aimed by the time the star moth is within range.

Pim watches as the two craft come screaming towards each other, pulling out two arrows and letting them fly the moment the Moth is in the furthest extent of his range, he does the same every few seconds as he waits for the craft to get inside his optimal window:

Round 4
Attack 1: 15 Damage: 7
Attack 2: 17 Damage: 6

Round 5
Attack 1: 14 Damage: 9
Attack 2: 13 Damage: 6

Anoushka curses fluidly in gith, just a running stream of commentary that would turn a githyanki's ears blue, and make a githzerai's fall off. She stands at the forecastle, watching as the Moondancer slowly turns, then moves to one of the ballistae, hollering for Glim to get up here and help. Even at far range, she encourages firing the ballista.

Rounds 1-2: Get to the forecastle, curse a lot.

Round 4: Make sure Glim and Wreji are coming to help man the ballista. Also involves cursing.

Round 4: Help to man the ballista and get it ready, with Glim and Wreji. She will take the aiming task (+7)

Round 5: She shoots the ballista (in game log, at Disadvantage): 

11 to hit for 12 damage

She cusses a lot more after it (probably) goes wide, directing the others to reload.

Round 4 (con't) - Pim drops another of the figures topside (2 of 4 down)

Round 5 (460') - Pim sends two more arrows, dropping a third figure topside. Glim finds two brave townsfolk to help with his ballista (roll to hit!). Anoushka takes charge of another ballista, 'directing' Wreji and another townsperson but she doesn't have the feel for the weapon and misses the star moth completely. Nip...
 - Although the party has managed to take out the crew of the mangonel, you discover the star moth has two ballistae in alcoves in the bow as two huge bolts come flying towards the Moondancer!
 -- Attack 1 vs AC 15: 16 Damage if hit: 13
 -- Attack 2 vs AC 15: 13 Damage if hit: 9

When able Wreji will cast bless on his nearest party members to aid in firing the ballistae. “I’m starting to think I should’ve taken up archery or firearms over swordsmanship hehehehe”

Nip will aim for the elves manning the ballista 

attack 1 Attack: 29 Damage: 14

attack 2 Attack: 21 Damage: 14

if either hit, add 3 for the swarm

Nip brings down another of the figures manning the mangonel. Wreji blesses Anoushka before she aims... (adding 2 to the attack roll. The star moth is AC13, so maybe?! Ahhh, but the damage isn't above the damage threshold, so it doesn't matter this time. =(

Round 5 - Still need Glim's attack with the ballista (with bless...)

Round 6 (375') ; Moondancer (-87 hp) ; Star moth (-0 hp):
 - Party is up!

Pim is in a machine, moving with practiced fluidity, watching as the distance closes, aiming for the crew working the war machines, calculating angles and waiting for the right moment..

Attack 1: 25 Damage: 11
Attack 2: 11 Damage: 6

Nip will continue sniping at anyone manning a ballista or monoalgal.

Attack: 17 Damage: 9

Attack: 22 Damage: 9

If either hit, the Swarm will feast for 1 damage 

Round 6. Still out of range for Eldritch Blasts (240’), still at long range for the ballista (120’ is reg), but blessed, Anoushka shoots with the ballista. (In game log)

13 (9+4 from bless) to hit for 16 damage

She cusses again just for good measure. 

“A little less profanity? A little more hitting the target yes?” Wreji says playfully, he’s enjoying this somehow. (I’m assuming as I continue to man the ballista my actions are limited yeah?) 

When the crew of the enemy mangonel falls, Glim cheers. He helps his "crew" aim & fire their ballistae at the moth. (round 5)

Round 5 ballistae: Attack: 17 Damage: 16

Bless Boost: 4

 The bolt goes *wide* of the target.