As some-one who's only been to duna twice, the jool system on a flyby lolprobe i didn't expect to get there and that planet closest to the sun but got stuck there, the biggest issue I have is how you (in stock) just have to eyeball if you have a transfer window and that's really only if you've seen a youtube video on how to do it. Without the video and next to no knowledge of how to go interplanetary I guess the only way to maybe get an intercept would be to drag out the poopy maneuver node all year till it gets a hit, and that's far too much time to do that even with time warps.
Maybe there is a tutorial for now, but when I played and learned how to do it there was none so I can only judge on what my experiences where like. I could download mods to make it more clear, but I've moved onto other games instead.