I have the same hair type as you (3a) and often come across this problem!! When I decide to grow out my hair It usually ends up stringy/ wavy. I was somewhat successful when using a light amount of detangler and mousse.
Your hair looks so pretty as it's grown out, I think you should consider if you really want to cut it. I usually decide to cut my hair when my life gets hectic (less hassel!)
My vote is to keep growing it!