That 50 ohm resitor will worsen the regulating output. It forces the upper IC to have higher than 5V output but regulation depends now on the resistor.

Have you had a look at TPS565208? It is a chip with low noise and ripple, easy to use SOT-563 package, very small footprint and cheap. I would not mess with any Linear, heatsinks, wall adapters etc.

Only downside (maybe) is that it accepts only up to 17 volts DC. But if your source is upt to 12volts your are more than good to go.

Ioannis