I've put just under 200 hours into KSP over a couple years. I've been to Duna and its moon, and on my current Science playthrough I'm about to hit up a low-orbit pass of Eve followed by a landing on Gilly (mostly because the ship I put into SOI edge orbit turns out not to have the DV to get to Moho).

What messes with me is actually getting the encounters with other planets. I've tried using launch window planners, simple planetary phase and ejection angle calculators, and I still haven't got the hang of things. I futz around with the maneuver nodes forever, never get an encounter, get bored, and give up. I know that certain other celestial bodies will require a mid-course plane change in order to actually put me in their orbit, but how do you determine when such a plane change will actually get you your encounter, when in order to get to the point where you're executing it you've probably been in solar orbit for the better part of a year or more?

The videos I've watched where people visit other planets mostly consist of them just saying, "Play around with the maneuver nodes, you'll figure it out." The Hell I will. You vastly underestimate my incompetence, friends.

This most recent playthrough I've tried MechJeb for the first time, mostly because I heard tell it would handle Kerbin takeoffs for me, because having to sit there and babysit the angle of attack on yet another rocket makes me want to die. I can tell MechJeb to plot me a course to another planet, but when it does, it never achieves an encounter on the first node, and I have to subsequently tell it to fine-tune the closest approach and do a follow-up burn. Is doing two burns to achieve an encounter normal? I am generally suspicious of having MechJeb do these sorts of things for me because there are times when I can pilot more efficiently than it can, so I wonder how much extra DV it's expending. I also have vague feelings of 'cheatiness,' using it for something I can't consistently do myself (unlike taking off, doing Hohmann transfers to Kerbin's satellites, landing, docking - I'm good on all of those).

tl;dr: I cannot for the life of me consistently get encounters with other planets, and can't figure out what I'm doing wrong, and the Internet has not helped me because I am bad at this game despite how much I enjoy playing it. Thoughts?