...now I feel compelled to make some of the Tyrian weapons into mech weapons.

Or just the Banana Blast.

I'm still working on it, while also bouncing between a Tyrian 2000 playthrough and working on a couple other small mods. The hard part is finding encounters to test the sprite replacements once they've been made; I actually have a Rustick replacement (including a new beam sprite) in the pipe, but for the life of me I'm turning up empty when trying to find them in the wild.

As to the heavy drones, we'll see. I'm mostly creating this mod as a small improvement to my limited spriting abilities (cutting and aligning sheets, adjusting .frames files), and I haven't looked into the heavy drone to see if it's made of parts (the way turrets are), which will be a challenge for me right now. But I'm trying.

can you replace the others like chiropterror and heavy drone?

Cosmostaches are mechanical squids with flexing Moushatches

I mean, the Cosmostache was already pretty ridiculous, so I felt they were the perfect target for the carrot ship sprite. Fits their ramming attack, too.

Evil Space Carrots