Mission president said “No.”
Church organizations are run a certain way. With the exception of RS and Primary, they are run by priesthood holders, and even those run by sisters are guided by priesthood holders.
If a business were structured the way the Church leadership is structured, it would face legal action for not promoting gender equality in leadership positions. But the Church is not a business. It is a religious organization lead by prophets and apostles who receive direction from the Lord. The Lord in His perfect understanding and infinite wisdom has structured the Church the way it is. We need to remind ourselves that His ways are not our ways.
So sisters wearing pants to church sounds like an interesting idea, but we would be remiss to think that doing so will promote sisters to Church leadership positions typically filled by men. In the same vein, no amount of pressure from gay organizations will make the Church accept gay marriages. The Lord is calling the shots on leadership and doctrine, not man (or women).