Machining Equipment, spline, file transfers.

We use engravers, laser cutters, routers and waterjets to use artwork from Illustrator.  I’ve been told by production that saving this as a .dxf (kind of works), but that their is no spline that a traditional CAD program might have.  I’m wondering if there are any better conversion methods that exist or that could exist that could better convert the curves/paths of items to manufacturing equipment as listed above.  Once upon a time there was Gerber and Omega but this sort of fell apart and was never upgraded.