Electric guitar...

1st I figured out what my goals are, do you want to be able to play in a band and or jam with friends ? singer songwriter? accompany yourself and or singer ? play at a campfire type thing or just learn your favorite licks riffs and solos most fall under the last but would have problem doing any of the others.

So each one would take a different approach on what you need to know and practice.

I'd would also get a drum pad and sticks and learn the basic drum rudiments with a metronome rhythm and counting helps so much this will help your playing a ton.
Kind of like a kid going to college you start studying for one thing but life changes and it becomes something completely different..
At my age I probably missed my window for playing in a band and certainly no one wants to hear me sing I'm sure of that not even me...
I think like you said the ladder just play my favorite rifts and solos and start puzzling it all together at that point into songs and so forth... When I see people doing looping and stuff like that and playing along to their own pre-made rhythm I kind of like that as well...
I'd like to practice for 2 to 4 years just kind of getting comfortable with the guitar and then see where it goes from there...