McCalls M5661 Muslin

So I really want to make the lovely blue top in this picture. Since I'm a completely new size I decided to make a muslin which I never used to do and to make view A since it used a lot less fabric and would be quicker to determine what changes needed to be done. I made a size 24 even though a smaller size might have done according to what I've read about the pattern (pattern sizes are way off from ready-to-wear sizes).

Here are the results.

My first thought was that it was way too big and that I should have made the 18 with a much larger FBA. I currently wear a 36DDD bra that probably needs a larger cup size and can wear my 34J that I have from nursing the nerdlet, but I'm hoping that when I wean this time I will be in a 36DDD or smaller so I'm being cheap and stubborn about it, but from my rib cage under my breast to my waist I expand (as you can see in the pictures) so I rounded up from my waist size. I have decided instead of going back to a size 18 and modifying from there to modify the 24 and see if I can't get it to work.

Here are the pattern changes I made. I decreased the length from the shoulder to breast by 1/2" all the way across. I straighten the shoulder to almost straight across since I have very little slant in my shoulders across. I put in a large sway back adjustment (doubling the typical suggested amount). I increased the curve on the sides to 1/2" smaller 3" below the side bust dart on both the front and back pattern pieces. I decreased each back pattern piece by 1" across. I am also planning on changing the back buttons to have a back seam and button or hook and loop at the top.

I've drawn out the new pattern and cut out the fabric and hopefully will have the new muslin done fairly soon. I've never had to do a third muslin before, and I'm hoping this one is a wearable muslin when finished. I plan on finishing the first one if it fits my sister S and she likes it (not sure how likely that is).