If it spawned later than it does, it would be pointless - by that time what use could you have of cannonballs and rotogun rounds?
I haven't hit this mission yet and although ive started playing a new game under N1 ive got to say... with my strategy and the way I do things ive got Very Little use for Cannonballs or Rotogun rounds personally. I jump right to Pyrotechnic Cannonballs before I pick up the assault cannon pretty much, and the Carronade is a heavy aerial weapon not a light weapon. Unless there's a Boarding Gun that uses Rotogun Rounds they don't sound that useful. By the time I could try and make swiss cheese out of some buildings with one ive probably beaten the map some other way.
(I use Grenades alot... OG X-Com taught me well) If I wanna go full auto on dudes at 7 tiles or less - probably just use some AMG I snagged off of osiron jerks since they sit around gathering dust.
Most effective weapon in og x-com and in a similar way in piratez is the HE Grenade and maybe incendiary grenades. The HE rounds for the heavy cannon and maybe auto cannon were barely entry level. I always had 2 grenadiers who would blow up pretty much any threat that my HWP spotted. Close actually counts with grenades. And as an indirect attack there's a good chance no reaction fire either.
The only way to nerf grenades in x-piratez or x-com would be to enable a Linked Attack to inflict D&D style damage with them so everyone in a certain area of effect takes a spray of fragmentation and it only hits them for maybe a rifle shot worth of damage. The d&d stats were 4d6 for the entire thing even if you landed the grenade in the dude's square, piddly 14 points and that's all. Personally id make it hit the dude in the square, then hit him again (8d6 total) for being in the area of effect.
OXCE doesn't have Linked Attacks yet though.
That's where you get shot with some needle dart doing like 15 Bio damage and if the dude takes any points from it at all, he gets hit for 150 damage from the Nerve Toxin VX shit thats in it.