I’ve also got a 3D Touch, not too dissimilar from your 3000. Although it’s had many, many problems, the one you’re describing doesn’t seem to be among them. It should be fairly easy to tell if it’s a mechanical problem (sticky linear bearings, slipping belts, etc) but in my experience these printers are mechanically robust and electrically weak. I would echo Eddi’s suggestion of switching to kisslicer, it’s the only way I’ve ever managed to get a half decent print out of it. I’ve also added a heated bed, upgraded to E3D v6 hotends, and am in the process of installing a Duet controller board, just to get something that prints reliably. So, in answer to your question; obsolete or salvageable, I’d say it depends on how much time and money you’re willing to spend on salvaging it.
Best of luck