These are suggestions that I wanted to suggest in the original mod.

The recipe requires a nuclear reactor, and it permanently places a tarantulator-specific reactor in the equipment grid. It would be nice to have an option so that the reactor of the recipe is only used for powering the movement of the tarantulator, so one can use a different power source for grid equipment. This would also solve a current inconsistency that I noticed: with spidertron fuel enabled, movement requires uranium fuel cell but internal energy production is unlimited.

Similar to the previous suggestion, it would be nice to reduce the number of single use specific recipes by integrating the vanilla railgun ammo into the tarantulator. Perhaps unlocking the railgun ammo earlier if the tarantulator is researched before the vanilla railgun, or adding an option to require the vanilla railgun research before the tarantulator.

And as personal preference: the grid could be bigger, perhaps 10x12 or 12x12. (Mech armor is 10x12)

The current version works great and with these suggestions I think that the tarantulator will turn just perfectly integrated into Factorio 2 and Space Age, and feel more natural or vanilla-like.

Thank you for your suggestions!

Regarding the energy production inconsistency: that's not quite true. The internal energy is completely canceled if there is no fuel left—it is tied to the fuel bar displayed beneath the fuel cells. Once this runs dry, no energy is produced in the grid anymore. Since I know the code, I can say with certainty that this is the intended behavior of the original mod as well (although I can’t comment on whether it ever worked in the original version, as I never tested it). That being said, it would certainly be possible to add a mod setting to separate the two.

As for integrating the vanilla railgun ammo into the tarantulator—I actually already had the same idea! However, for now, I’ve decided against it for consistency reasons. It’s still on my list of possible changes, though.

The grid size is another aspect that is already on my list. I just wanted to gather a bit more feedback and do some test runs myself first (which I haven’t had time for yet).

In any case, I always appreciate constructive feedback. Thanks again!

You are right about the energy part, I was sure that I saw it generating free energy but after testing now I just saw how the tarantulator uses nuclear fuel to recharge batteries.

It's good news to see that you have the ideas in consideration, please keep considering the use of the native railgun, I'm also asking to have Krastorio's railgun integrated the same way, that mod introduces more variations of the railgun ammo though. If that succeeds then the native railgun turret, Krastorio's railgun and the Tarantulator could end up using the same railgun ammo, including the explosive and antimatter option of Krastorio if available.