Yes neither one of them are going anywhere and if they do then the whole cryptosphere is in a world of hurt. A lot of the problems that you mentioned about bitcoin won't hurt the investor at all and may actually be beneficial for them in terms of a hardfork, and then receiving the new BTC coin (whatever it maybe) and keeping their original one.
I'd be comfortable with a 50/50 split.
Interesting perspective, thanks for sharing. Which coins are you most interested in at this time?