Something interesting in an article by Cubicle 7. Their latest rpg piece is about soldiers within the Empire (State Troops to Knightly Orders) but it also looks at mercenaries in Tilea (and other Dogs of War). Does the front cover give us any look at mercenaries? Yes it certainly does (biggest image I could find).
If you don't know who the mercenaries are, two of them are just random but three of them are from the Alcatani Fellowship!
These mercenaries are from the Dogs of War army book (5th edition) and are famous enough that their leader (Roderigo Delmonte) and the Fellowship are on the front cover. Definitely interesting to see their designs still being used in modern lore (hope CA and GW remember the Alessio Cavatore Official list which added generic mercenaries).http://sactosaws.com/SAWSChallenge/dogsofwararmylist.pdf
The last part I want to quickly mention are Knightly Orders. As it mentions "A guide to the renowned knightly orders of the Empire, with options for joining secular orders, templar chapters, or going it alone as a freelance knight."
and that we're missing Kurt Helborg, Ludwig, Grand Master, etc. I was thinking that a 'Create your own Knightly Order' would be decent considering we have the create your own Daemon Prince. Colour scheme, Grand Master loadout and stats, the Order's attributes and background from monstrous cavalry, on foot, mercenary, etc. Warhammer 40k has always had the appeal of creating your own Space Marine Chapter and Warhammer Fantasy could have it too.
Making your own Mercenary General would be excellent too.