Instructing is always invaluable experience. I learned so much with as little as 200 hours dual given. I can only imagine how much you would learn with 500-1000 dual given.
I questioned myself, as whether I wanted to spend 6k to go do a jet bridge program, or if I wanted to pay for my CFI. I took the CFI and I don't regret the decision at all. MOST airlines want to see that you have instruction experience; ASA is not necessarily one of those airlines. All majors are going to look back and see where you got your experience. Its always good for them to know you can lead by example and be a teacher. Whether your good or not, well thats for you to decide.
With that said. I am a low hour pilot, 500 hours, and I have gotten picked up by a regional. I didn't expect it though. You can always try and see what happens.