Let's say a Guild Hall is composed of two rooms :
-A guild would need buy a "PvE" sigil for a fixed sum from a marchant to get the PVE room.
-A guild would need to win a celestial sigil in the HoH to get the PVP room.
The first sigil your guild obtain would create the Guild Hall and the corresponding room. Obtaining the other sigil would create the second room.
Guild players wanting to do PvE could meet in the PvE room. Likely, Guild players wanting to do PvP could meet in the PvP room.
If this is implemented, A.NET doesn't need to allow trading of celestial sigil anymore. The PvP room would have to be won by hard PvP labor. Same for PvE room (gathering enough gold). That way, I think both PvP and PvE players would be happy.

What do you think ?