I still swaddled my DD tightly like a mummy, she loves it, for nap times and bedtimes, it works well.
Re the bathtime, my DD splashes constantly and laughs, I didn't think it would be relaxing, but as soon as she is out of the bath, gets in her sleepsuit, she knows its time for bed. I give her a bottle while singing a lullaby. When I get the swaddled ready, she is grinning like a cheshire cat, as she knows it is time for bed. She goes out like a light.
I think when my DD splashes about it is to release the tension, and preparing herself for the long night ahead.
HTH