Good mod overall. I've been looking for a mod that adds a Spidertron with a different and beefier look to it. However, a couple thoughts:
-As other users have said, the price may be a bit too cheap; an alternative could be to reduce its health and armor and maybe swap out its artillery cannon for a normal tank cannon? You could then potentially give it its own tech that isn't quite as far up on the tech tree (maybe just requiring red, green, blue and grey science). If it has smaller-scale weapons and a smaller health pool/armor, the cost would probably be more balanced and allow the player to use swarms of them as heavy-duty attackers that can be controlled remotely. On the other hand, the fact that it requires fuel helps bring it back toward being balanced.
-Twin machine guns and a regular tank cannon would also be neat - maybe this could be yet another variant provided by the mod?
-It seems to only fire the weapon that is currently selected when you pilot it, even when it is unpiloted. I was sort of hoping it would fire all of its weapons simultaneously if it had ammo for them; seems like this might become more of a problem if you need to switch its current weapon remotely - you'd have to meet up with it and enter it to change the weapon it's currently using.