here's the two books i learned to pattern from:
basic pattern skills for fasion design - bernard zamkoff and jeanne price
how to draft basic patterns - ernestine kopp, bittorina rolfo, beatrice zelin, lee gross
oh i would recommend nixxing the raglan sleeves if you're not in love with the idea. they're really hard to pattern. the whole concept terrifies me! but if you're brave, more power to ya! cute dress! one thing i noticed in the picture is that the side seams sit at the front of the arms eye instead of in the middle. that might be hard to work with, it may require lots of trial and error. if you feel like you've gotten the pattern right make it first in cheap-o fabric to see if it hangs how you want. i hope i could help! good luck!