It's something we've thought about in the past, but really, like some other stuff (World Devastators being the prime example) it potentially wouldn't work that well in EaW. All the Proton Torpedoes were fire-linked and could only fire at planets effectively, but on the other hand that doesn't really match with the information that one was being used to
defend Corellia or how effectively Pitta was apparently able to use it against Aggressor.
As an addon it were never widely used
Eh, this is kind of questionable. There's a few pretty high-profile engagements where it was used, and although it was rare in the time of the actual Empire, it seems like one of the few ships that became a lot more popular in the Remnant era (especially given that the Empire had apparently at least started building hundreds more).
And if it would work somehow like the deathstar did in base-game... well... it was a broken thing to begin with. The main problem with DS as a whole is there is basicly no way to counter it.
The Torpedo Sphere is much, much smaller so if it did exist in EaW as a combat ship, there's no reason it wouldn't be able to be destroyed or function in a conventional way. It wasn't meant to destroy planets entirely either, just be a dedicated siege platform, so that part isn't a factor.
Dave's assessment of what we tend to go for is mostly correct, but a few points there to clarify as well, since the Warlords especially provide some unique scenarios.
Ships with clear statistics and/or known design are preffered. Mostly if both exist. if both of these missing... god help you.
Basically, the idea is if we're going to add something, there needs to be something to add. If there's no statistics and no picture, it's not even a case of "this ship looks cool" prompting people to want to add it. It's usually the clearest indicator of "let's just add literally everything we can find a link to on Wookiepedia." Either that, or somebody thinks the name of the ship is
super cool, and that's no reason to work on designing and carving out a role for a new ship. Which leads us to...
Would it make sense to give it to any playable groups/ was it widely used troughout the galaxy?
Would it bring anything new gameplay wise for any faction if not all. Like PA's Preators, which means if you have borders with them you have to prepare something against those beasts...
These are sort of part of the same criterion for us, and they both tie into the preceding one as well. Basically, we don't want to just haphazardly throw a bunch of random units into the mod that all do the same thing; leaving aside redundancy and over-crowded build bars, if we ever want to change or fix something, it becomes much harder to keep track of everything. This is already an issue in the mod, where any eventual possibility of death clones, for example, is more or less already out of the question solely as a function of sheer volume, and when we want to remake the worse models there's now far more to be done.
It's all a matter of priority. Basically, if something's not bringing any new gameplay options to the table, why would we do it over something that does, or redoing something that looks worse in the mod? There are plenty of people who would respond to "do you want unit x, unit y, or to redo unit z?" with "simple "yes," because to a lot of players it's just "LET'S DO ALL THE THINGS!" For us though, the amount we can do is proportional to the amount of people we have, so it's a question of what we can actually do with our resources, which are then allocated according to what adds something new, or what's detracting from the game already (ie, poorer model quality in existing ships or incomplete features).
That is the context in which we care how widespread something is in the SW Galaxy. As long as somethign had at least some regular use, meaning it wasn't a unqiue ship like the Eclipse or it's not part of its lore that it's limited in use like the TIE Phantom, we're not against having rarer ships. However, if we only need one ship to fill one role, and we can't do multiple ones, the VSDII is always going to have priority over the Procursator, for example. The Warlords kind of throw this off, however. We're now able to split the Imperial roster across 5 factions, so redundant units can more easily be spread out, and something that's just a visual as opposed to role-based difference may be enough for something to be considered for, say, Maldrood when it wouldn't be in contention at all if we just had the Remnant.
If you are good at 3D modeling/animation and offer to do it yourself, it might just give you a huge advantage though I don't think it would guarantee success.
This is actually a complete non-factor unless you're actually joining the team. If someone already know how to do 3D Modeling and stuff, and you wanted to help make that content, presumably that person would be joining the tea anyway. Otherwise, if it's someone who doesn't know how to model already and they're just doing that one ship because they want it in the mod, not to be mean, but I doubt we'd take it anyways. We've spent years working on replacing our own old models from when we were worse, and that process will be ongoing for however long we work on our stuff; we'd be extremely unlikely to take someone else's first time work, since it would be very unlikely to measure up to the standards we're trying to set.