Picture
We all know we have hosted a bridal shower for a friend or a family member before.  I think we just do what we figure needs to be done a wedding without a wedding shower is most likely unheard of. (no matter how small or big)

According to Jan Wilson and Beth Wilson Hickman "A show is usually hosted by a friend, friend of the family, or the maid of honor and/or bridesmaids. A mother or sister should not host a party where gifts are expected."
 
Picture
Statistic has proven that when a bride-to-be plans months in advance for her big day, not only would she have able time to change her mind many times over but it eliminates a lot of unnecessary stress in the long run.  Therefore the thought for today from the "Romance Diva" is "Planning early reduces a lot of unnecessary stress later" 
 
Picture
Yes you can choose a male bridesmaid and a groom may choose a female "groosman" as well.  I would suggest you both discuss the situation and you both are ok with the idea.  In regards to the attire I would suggest that this opposite-gender attendant wear the approprate attire.  (dresses for females and suites or tuxes for males) They can stand on either side of the altar.