I'm pretty sure Kalo wants to do them, and most of the rest of us are at least neutral to the idea. Haven't done one of these non-Dev-Diary Wall of Text posts in a while....
Depends who and when you ask, and how many resources we get. We're reluctant to go too far off the grounds of canon here, for one thing. When deciding how to deal with factions we tend to take an approach pretty much inspired by how the Total War series picks factions and time periods. Basically, are they in a position where the right chain of events could put them in a position of at least notable power? Is there something unique stylistically about them, aesthetically or playstyle? Also, for us, is there enough canon information to work with?
With the Empire of the Hand we explicitly wanted to cover a very large and obviously powerful faction with a diverse military that just didn't get much attention in-universe, as well as providing us a way to be creative. With the Ssi-Ruuvi, they aren't the biggest faction but they're extremely expansionist, unique, and have a mostly-developed military, with very clear themes we can extrapolate from to make the ships they need (especially on the larger end) as a sort of "what if they hadn't gotten absolutely facerolled by the Empire of the Hand, New Republic and Yuuzhan Vong before they could make any progress" situation. The Vong are the Vong. Unique, fleshed out, and considering they almost conquered the whole galaxy they were certainly in a position of power. Also, considering the focus of our work (Thrawn, the unknown regions and the Empire of the Hand) the absence of the Vong and Ssi-Ruu in ICW and Ascendancy is a pretty considerable hole.
The Hapans, on the other hand, are a bit of a different harder to commit to either way. Territory-wise I'd be willing to say they qualify, if only just. They had 63 inhabited systems, which doesn't sound like much but by the start of the Vong War the Remnant had at absolute most 400 (50 per sector being the definitional limit, and they had 8 sectors). The problem there is that they weren't really looking to get beyond that. They were pretty much happy to always just be the NR's little brother and the junior-junior partner of the Galactic Alliance. Stylistically there's something there, artwise. The biggest draw for me is this mental picture I have of large, ostentatious fleets, and something can probably be done with the Battledragon Wall and social hierarchy to build some sort of uniqueish playstyle. The biggest drawback is the lack of canon material to work with. Enough has been mentioned to know that they don't *just* have Battle Dragons and Nova Cruisers, and that in order to build stuff like Song of War and Star Home they must have pretty decently sized shipyards somewhere, but as far as ship classes go we on;y have the two designs to work with, and we'd need to make up everything else which is a pretty big workload.
I'd say it's a lot more likely if we had at least one more good concept artist and another modeler/skinner, or if we get really far ahead with the other 3 factions (which is fairly likely but depends on how much EotH stuff needs redoing). As it is, the art "department" on the team is Slevered, Davis, Kalo, Codeuser and myself. Kalo's been busy with school, and hasn't been able to do much recently, though he was actually working on a design for the other canon Hapan ship (the Beta). Codeuser's pretty much the same; he'll occaisionally contribute a model like the Acclamator most recently, but when he's working it's mostly on particle effects. Slevered and I are pretty occupied with the other aspects of the mod (I do all of the coding and map design and whatnot, while he's been doing a lot of the UI work in OzWolf's absence), and we'll probably be the main ones who work on redoing Empire of the Hand assets that need it. Davis is the best of us at organic shapes, so he's pretty much always working on Mon Calamari, Ssi-Ruuvi or Vong stuff.