Mass Effect 1 retail vs Mass Effect 1 from Trilogy / PC

Are you talking about the PS3 version, or the PC version?  Can't speak for the PS3 one, but on my PC the only difference I've noticed (and I have both the original retail disc and the recent EA/Store digital download, but not the bundled "Trilogy" version) is that scanning uninhabited worlds and moving between systems was made a whole lot simpler.  (No more wearing my mouse out spinning a planet under the scanning reticle, thank God!)