Potential Shooter Loadout

only use 1 mortar-like item
switch the ballpark mortar for a sniper or E cannon
now your loadout will be
firebomb
sniper
cannon
E cannon
the firebomb will signifigantly buff the cannons

 

But I don't have any explosive cannon

 

than use a heavy splash like a big torpedo, or use a long cooldown heavy damage weapon (aka railgun)
or you can use a mortar is you replace the fire bomb with a flare

 

Just load out your ship with weapons that you play best with. Who cares if they're all torps or all mortars, even all cannons, it's gotta suit your style. See i prefer napalm, mines, torps & mortars because those items can damage a few ships at once & keep you safer from a distance or behind rocky formations.