Wrap Dress Muslin

I've been working on this wrap dress muslin for a while now. I find that when I run into significant fit issues it can make my mojo dry up faster than the speed of light. I've been consciously 'forcing' myself to sew for a minimum of 30 minutes a day, so that I can push past this point. Once I have these issues worked out, then I know I'll be fine. I have a number of knit pieces that would work beautifully in a dress like this, so it's worth it to me to get the pattern adjusted properly.

Initially I was inspired by dresses like this Diane Von Furstenberg dress (which I know is sewn from a woven):

DIANE VON FURSTENBERG Starred Clouds Coral Silk Valencia Dress 

Pattern: Ottobre 05/2013 #17

Size: 52 (although I may need to be sewing a smaller size in future)

Muslin made from Peacock poly-knit

Alterations made BEFORE cutting muslin: 

• Added 1" to sleeve width at bicep
• Extended front to be a full width piece (faux wrap) and cropped the under layer
• Added 1.25" to back side seam at butt level

Observations: 

• Dress is far too wide at neckline, bra straps are showing. 
• Dress is FAR too low at neckline - entire front of bra is showing
• It just feels too big overall - especially around the neck and shoulder area
• When I pulled the front crossover tighter, it pulled the side seams to the front, so I can't just do that...there is a chance that I pulled too much across. Perhaps I could do this if I only shaved off a little. 
• It almost feels as though I want to make a honking great dart on the underlayer to pull it in tighter. 

Alterations which still need to be made: 

• Raise neckline (ie. insertion point at side seam) by about 3 - 4"
• Bring in shoulders (reduce neck width)
• Remove length from skirt - not too much, but it is currently at granny level for me
• Bring in side seams, particularly at bust level
• Perhaps sew a smaller size, especially around the neck/shoulder area?
• For summer, sew a short sleeve, perhaps flare the skirt and the sleeve?