So here is my two cents. I am an AD guy getting ready to transition to the reserves/airlines in a month, so take it for what it is worth. I did ROTC for three years. I hadn't planned on going that route, but it worked. I joined without a guaranteed pilot slot, but I figured I had a shot. Here is what I did to make sure it happened, if you do ROTC I would recommend the same:

Got really good grades. Granted, I was a history major. But still, get good grades whatever your major. Along with this, study for the AFOQT. Ace it, and that will go a long way to getting a slot.

Worked out like a mad man. If you can ace your PT test, that is huge. It shows commitment, and proves to them you are not a slug.

Worked hard in ROTC-did all the gay stuff from extra PT sessions to extra activities like flag details misc stuff etc... I didn't let it ruin my college fun, but I was in the building a ton my first year. I got noticed by the cadre, in a good way. They will go to bat for you if you try hard.

Did extra curricular stuff at school-played lax and fooled around a bit with student government. It looks good for you if you have some of this type of stuff.

So I busted my a$$ for a year, went to field training and then did my POC Jr/Sr year. Got the slot at the end of my junior year if I remember correctly, or maybe it was the beginning of senior yr, I can't remember.

Now, having said all this, in hindsight I would have done nothing in college but play. I would get a reserve/guard job and get the guaranteed pilot slot. I look back on ROTC thankfully that I was naive enough not to worry about the possibility of not getting a slot, and lucky enough to get one. Either route you go, good luck!