Tell us about yourself!
Not at all! Actually that would be the experimental way to evaluate future notable points between the planets. And when you´re done, just go back to the current date.
Not in relation to distance from the Sun Guus. That would make it impractical as you correctly pointed lot. But in angular relation. For example, if Earth is on angle 90 today, what angle position should Saturn be? This disposition wouldn't involve any new crafting but would allow you to forecast visually when a planet is near Earth or when they are near each other.