New straps? Check.
I also discovered that one of the old straps was about an inch (2 cm) longer than the other. These things happen when one sews in a hurry. The new ones are the same length.
No more pleats? Check.
This was a fiddly fix, and a few rhinestones had to come off the dress in the process. I ripped out the elastic in the two affected areas to separate the bodice and bodysuit somewhat, and then ripped open about two inches (5 cm) of seam down from the top edge. This let me reposition the seam to remove the excess fabric. I sewed the new seam on my machine, and then went over them by hand to smooth out the transition between old and new seams.
New underskirt? Uuurrrr . . . not quite check.
This particular dress has a two-tier underskirt, with the upper tier attached directly to the leotard. The upper tier is one circle, and the lower tier is two circles with a very long hemline. My original intention was to have two layers in the lower tier, but I miscalculated the amount of fabric I needed by about half a meter. I have since then acquired the fabric I needed, and I have cut out and sewed the panels for the new underskirt. I even attached the crin (the miles and miles and miles of crin . . .), and then this happened:
I am new to the ways of the serger, and still learning how much thread it consumes. Eight spools has gotten me far in this project but not far enough. The new underskirt will be attached when I have more thread.