When you use the term "non-WAAS", do you mean "non-approved"? Your query makes much more sense to me if that's what you mean. From what I'm hearing, it sounds like you are talking about an airplane with conventional nav, no DME, and an Aera unit. So it is a "\U" equipped airplane, equipment-wise. Although fewer in number, you can still fly IFR and there are still approaches you can do in a \U equipped airplane. Although technically, the Aera may be able to give you guidance to waypoints, you legally cannot declare the ability to do that. I've never used an Aera but I doubt it has approaches or approach waypoints in it's database, so you may not even "pretend" to do an RNAV approach. So, just use the for non-DME, conventional approaches. (Use the Aera for situational awareness). As long as you do them at airports that have such approaches, what's wrong with that?
FWIW, WAAS is not a term that means the unit is approved. Both WAAS and non-WAAS units are FAA approved. Although I doubt there is a WAAS unit that is not approved. Approval is something else entirely. If you don't know what WAAS means, I'm sure a bunch of people will fill you in.