I'd honestly like to see this new faction meet the Outcasts. Since that criminal house is based off of Italy, the two factions would share much in culture (at least), and even politics (at most). Still, Outcasts might trick them into trading for Cardamine, which can have very large ramifications in many aspects of Imperium Society.
As for underdeveloped tech and training... Personally, I find this distasteful, though understandable, especially if the Imperium didn't find any traces of artifacts in their core systems. You'd think 600+ years of civilization development would make the Imperium branch off to another technology-path not following Sirian tech.
Overall, this new faction intrigues me. While I could argue about the placement of their connection to Sirius (just look what happened to Gallia... Remote as [A.D.M.I.N. Censored]), this looks like a nice base for a new house to be developed on. Just add in other intra-faction companies, "criminal" elements known in the Imperium, more details as to their core worlds, some (primitively-)new tech and ship-designs, and it'll be a good house-kickstarter.