I would find it hard for anyone to say that you fucked up and are in a world of hurt in your situation. Seriously at 23 with a positive net worth and a job above the median income, kudos to you.
1) Do you have any plans to continue your education? If you do now is the time to do it since you are still in college mode. Once you get settled in post college, it will be much harder to get the momentum back once the next life milestones come, relationship, marriage, kids, ect. Do your best to get your employer to pick up the tab if you can swing it.
2) Very admirable to help your sister out, again with your financial situation, I can't really fault you with offering to help. I would have maybe done as an interest free loan. I'm with the skin in the game camp. If you had to work and take on debt to finish college, I don't see 12k as being a crushing amount of debt to complete college. For me it would give me a great sense of pride to know that I did it on my own, to a degree, without handouts.
3) With your other misc debt, a faster way to pay it off would be to get a part-time job. However, make sure your opportunity cost for taking on another job is low. Meaning your performance at your full-time job does not suffer, your expenses don't go up because you don't have time to cook, clean, ect.
I'll add a few things that you didn't explicitly ask advice on but might be relevant to your situation. Since you like to travel, to minimize your costs I would look into travel hacking. That 2.5k road trip could have be done in half or less if you would have signed up for some credit cards with sign on bonuses.
Also to keep lifestyle inflation down, you need to have a goal or a plan on what to do with your new fire hose of income. That is what most new graduates fall into when getting their first high paying professional job. I was always saver but after graduating college making 4x I have ever made, I started to eat out more, take nicer vacations, give more expensive presents, ect. Without a concrete short to medium term goal, I thought a 30% savings rate was more than enough for a 30-40 year career. Things would be completely different if I knew about FIRE in college.
Nice job, you are off to a great start but don't let up. You can be FIRE in less than 10 years and never have to work for money another day in your life if you choose to.