Pace
I have some sympathy for your opinion about the sate of the interior of training aircraft but the cost of panel replacement is BIG. By the time even a small panel reaches the UK it will be over £100 and with about 11 panels in the inside of a C152 that is a big cost especially when students have the habit of grabbing hold of bits of the aircraft that were never designed to be grabbed and breaking them.
As for the radio fit it is all a matter of opinion, a few weeks back I overheard a guy slagging off the radio fit in one of my C152's, the aircraft has a KING stack all of it working and all of it still available new. What does the guy what ? The new touch screen Garmin ? Hardly appropriate for a basic trainer and likely to push the price of a flying hour up be 25%.
Oh ! I forgot to mention that we are finding more serious structural issues on one type of 300 hour old light sport aircraft than we are finding on 14,000 hour C152's. it would seem to me that the thirty year old trainers are much better built than some of the newer aircraft, they may be slow and burn a lot of fuel but that is the price of having a student resistant aircraft.