Have better black boxes been invented that are near being used?
I’m thinking of things like recording more than one area’s conversations, maybe even security footage of the cabin.
Also, easier to find in wreckage. Flashing lights, sounds, exploding dye-pack, separate parachute, etc.
Surely lots of basement inventers would dream of hitting the big time and having the government mandate their creation on every flight.
Sounds like you need to get into your basement 
http://www.bath.ac.uk/~en9klf/fdr.htm
per this site apparently some already have some kind of radio signal that they can use to track/locate it.
If you ask me they should mount some kind of wireless phone type technology into it. Plane crashes, team shows up, calls a number via laptop/modem and download the data.
Sure, there have been new designs for black boxes. One ‘black box’ is called the ELT, or Emergency Locator Transmitter. Even small private planes have them. They go off on impact and start emitting a radio signal which can be triangulated.
There is a newer model that communicates directly with special search-and rescue satellites, and actually broadcasts its position using GPS data. So that’s one example.
But these boxes are expensive to design, and even more expensive to certify. And the current ones actually work very well. So there is little incentive to really make them a lot better.