This post may be a little late (only about 3 years) but still may have relevance.

To the OP, are you sure the reception on the ten dollar radio is as good as you may think it is? For instance, will it take the same amount of strong signal before saturating the front end. This can be a very big factor for many people but not at all important to others, all depending on where you use it. The 7600GR seems to have a very good dynamic range to me but you will never know it until you are in a position to overload the front end, such as being near powerful MW transmitters or using a 200' longwire antenna is search of the elusive weak DX station. Will the $10 receiver handle this as well as the expensive receiver.

As for well laid out circuitry, I don't know how you could pick a radio by looking at its schematic. Any number of components could be altered slightly and turn a good RX into a terrible RX or vice versa and you would have know way of knowing that by looking at component values.

Reading many opinions on a given receiver is about the best way to choose. Then once you have yours, and if you think it is not performing as well as others think that model should, the next thing to do would be to compare it with another one. If that is not an option you might set up some tests that you can have others repeat and see if you get the same results. The tests could be to devise a simple transmitter at a MW frequency and see how far away your miliwatter can be placed and till heard at all, or turn on the TUNE indicator. Then send your TXMTR to a friend and have him do the same, under all the same conditions of course. There are lots of ways to do comparisons long distance so to speak.

You can make a transmitter out of something as simple as a 555 timer I.C. and 3 resistors and 2 capacitors and a battery. Don't use a plug in power supply as then you would be introducing an antenna that is not the same at one installation as another.