I've been playing guitar for 15 years now. I've done work on cruise ships, gave lessons, recordings etc. etc. Kinda burned out on that aspect. I play for fun now, meaning I don't approach music as work anymore. To anyone that wants to truly get better at the instrument and doesn't have a lot of time to put in, you can still become a great player with the right time management. For example, lets say you only have a hour to practice everyday. That is more than enough time.
5 minute warm up
Scales-15 mins
Speed exercise- 15 mins
Sight reading- 15 mins
Work on a song you're learning- 10 mins
You can switch things out everyday. One day do sight reading, the next do basic theory work like building dyads and triads along the fretboard. It's important to understand what your goals are as well. If you want to write music and truly understand what works and why, you should learn some basic theory. Like the Major and Natural Minor scale, how to build dyads and triads, etc. Just simple things. If you just want to learn songs then take the short cut and learn how to read tablature. The last few years my focus has shifted to bass though. If anyone needs help or is taking ensemble in college and can't figure something out, don't be afraid to ask.
EDIT; and for the love of god..purchase a metronome lol. Timing is very important.