3 1/2 month old still wanting to be swaddled?

I have a 3 1/2 month old, and the ONLY way I can get her to sleep in her crib is to swaddle her. She is 24 inches long, so it's getting very hard to find a swaddle that fits her weill w/o bunching her legs up (I have 3 right now, but they are getting small on her and will not work for much longer). I have no idea how to get her to sleep without being swaddled. I am glad that it works for now, but when she gets a little longer- How do I get her to sleep without it? I would like to start now so that she is used to it, plus since it's the summer, I feel bad having her swaddled. On the warmer nights, I put her in a diaper and then the swaddle, otherwise she wears a onesie and then the swaddle. Any one go through this at all? Any suggestions on how to get her to not NEED to be swaddled? She fights her naps like crazy too, screams to keep herself awake, all the while falling asleep at the same time. I have tried swaddling her for naps as well, which cuts down some on the nap fighting, but she still sleeps only an hour. She sleeps through the night (from 10p.m until about 9:30a.m) but her naps are literally about an hour 2-3 times a day. Which, if that's why she sleeps through the night, that's fine. Lol. But I wanted to see if anyone else has experienced this as well. Any suggestions on how to get her to be ok with not being swaddled would be great! And any common stories on your baby's naps would be great too! :)