Has she applied to the majors already (particularly Delta)? Female aviatiors are considered diverse and are regarded as extremely desirable candidates for the best positions in this career.

Regardless, if going to a regional to improve the resume for a street hire at any major, I wouldn't worry about Envoy. The main gimmick Envoy has is the flow. If you are assured of a call from a major in fairly short order, there are better places to be.