I would like to die...
...with someone, definitely not alone...
...fighting, knowing that my death is not in vain and that I served a (the) right cause?
...or, peacefully, at a ripe old age, having a wonderful and inspiring life behind me.
Living forever... Faustian, indeed. But =so far= (emphasis!) I would lean to going on forever, as long as I'd be able to appreciate it.
The best option, of course, would be living as long as you want to.

(as long as there's enjoyable rep left to learn....

)