I say go for it !

Ignore the doubters and those that don't like the idea. just go for it I say.

It's a good idea and a fully workable one, I've been a hardware/software
designer for years and theirs nothing that's so difficult in the idea.

Though what I'd do is for the unit to have its own fast ADC - at least 18-bit.
and it's own little cpu - ATmega's are nice and easy to use. Then send the
current freq and log level down the RS232 port to a PC.

Happy experimenting !

Clive