Yes I am aware of the Gelgoog's capablities as a stand alone suit for it's era. It can still hang with some of the suits of this decade but I don't see anyone pulling a Judau Ashta in his ZZ (ZZ being a trash heap in victory). If there is merit to be had in certain suits appearing I have nothing against that.

At this point in time I am considering two separate Zeon factions appearing. The Sleeves being one headed by Full Frontal as you asked and another one being headed by a yet to be named fanatical Grand Admiral that helped Zeon back all the way towards the One Year War or maybe Haman's former Zeon. He gained support by being a rallying voice for those who didn't want to follow Frontal. I'm planning on him being a strong follower of Deikun but an stalwart believer in old Zeon ala Admiral Delaz. 

For my own character I plan on using a character I didn't get to use much of during a another gundam rp based on the one year war. He's not going to be a newtype highlights of his career will be majorly being a strong ace pilot after the war, serving with Titans briefly before defecting to Karaba, and some work as a lieutenant in Londo Bell. His suit has yet to be decided his code name being Grey Ghost.