I certainly stress the importance of the ki perspective in aikido training. Still, I would not say that it should be regarded as a kind of goal for the training.
A Japanese teacher once told me that the name of the art should sort of be read backward. Kara-te-do would then be "the way by the hand to emptiness". Ai-ki-do would be something like "the way through ki to joining/harmony".
I like the idea.
I don't really understand the question about long or short road. Every way (
) is a lifetime thing, and as far as I know there is no end to the progress one can make through continued practice. Neither with ki nor with anything else that can be gained through aikido training, there is a final level, a stage of development that is enough.
There is always more...
There are easy methods to sort of quickly awaken and increase one's ki, but they need to be repeated over a long period of time, in order to remain. I've written a book with such exercises, but I repeat on almost every page that they need to be done frequently over a long period of time, or the effect will quickly vanish.
That's not a bad thing at all. Repetition is the door to magic.
There's no point in getting tired of breathing.