With all these things, there's 'buggered' and there's 'buggered', with much depending on the degree of embuggerment. Disembuggerment of the mag and retention of 6v electrics is probably lower cost than a replacement ignition system, 12v battery, regulator, bulbs etc, and should be properly reliable too. So I think your instinct to stick with it is good. (I am, of course, biased.) But there are loads of options and you probably still need to do some www homework to be sure what will suit you best. There are advocates for all options on here and plenty of real-life experience of how they pan out in practice.