Alexandra isn't really much heavier than a number of WTA players. She needs to increase her quickness. I think some track drills would do her good.
But mainly I think she needs to concentrate on tennis rather than thinking tennis is the portal to a career in singing or acting. I don't have a problem with her wanting to sing or act, but why waste her time playing tennis then?
I think she could be a very good tennis player, but she has the talent to do more than she has done, and the only reason I can think she hasn't is that she hasn't put in the kind of concentrated work that she needs to do.
I hope this new English coach (what is his name?) is the ticket to getting her on the right track.