My impression is that Nullriver is really not active in fixing the issues with Installer, and of course, Installer is closed-source. I don't know how big an impact it would be, but Cydia got where it did so quickly because it's based on the extensively developed APT system, and is therefore subject to GPL. I'm not sure how well Nullriver would like complying with GPL as it would affect the inclusion of Cydia into Installer....