I suspect they'll show up in SP DLC at some point or another--though technically I suppose they already have--Bioware have always been consistent when it comes to re-using in-game assets.
The Omega DLC is a pretty obvious candidate given the significance of the Omega 4 relay. Personally I'm more curious if the Omega DLC will re-introduce the excised/trimmed-back "Cerberus are indoctrinated" sub-plot. By which I mean where a large number of TIM's troops were full-on indoctrinated by the reapers, as opposed to indoctrinated by TIM using reaper tech. It'd make sense that ground zero for this would be the collector base/remains there of.