While electronics is great fun
- I used to build everything in E&WW and other bits too -
I'm having trouble thinking of much you can build with a soldering iron these days that cant be done in code - apart from sticking on the odd sensor or so on. And the solder doesn't smell so good anymore.
Given that you can make a full recording studio on an off the shelf PC and practically run the world with a pic development kit or possibly a RaspberryPi the only thing people seem to make at 'home soldering' level these days seems to be rip-off add on boards.
The remainder - hi power hifi and mains control stuff is a bit out of most kids league.
Geda and lots of ngspice could be useful...