At some point you lose enough energy that your speed drops enough that your altitude starts dropping significantly. You can't lose the energy without losing altitude, and once you lose altitude you start losing energy whether you like it or not
I think what you are wondering is "can I stay in the thin atmosphere bleeding X Joules of energy for 50 minutes until most of the energy has gone rather than entering more steeply and bleeding 10X Joules for 5 minutes"
However once you lose energy, you lose your altitude, and as you lose altitude the atmosphere thickens and you start very quickly losing 5X, 10X, 20X joules every minute.
And then the wings would also survive the flip and vertical landing. Or if you want to land like a plane, then you also need landing gear.
So there is really no way to add wings without adding a huge amount of mass. You are building a completely new thing.
There are some super cool mega-space planes designed in the 70s (I think). But of course these were never built or even tested. I remember they had some overlapping metal heat shields and a big ass delta wing. They would also start vertically and use air breathing engines.