You can join your Custom Knighthood Order, but doing so has 4 big changes compared to the existing KOs: Their skills and attributes have to be upgraded several times so that they can be equipped with elite tier items. Note: upon creating your own Order, you won't be able to give any mount at all to the Sergeants, as they start with no riding skill.
While their stats and equipment can be improved, it will take a lot of money and time for them to become truly effective - once fully improved however, they will be an elite force that both suit your play-style and could potentially go toe-to-toe even with a Noldor Twilight Knight. Furthermore, both suffer from terrible stats, with the knights having 200 proficiencies, 18 strength, 12 agility and 3-3-2-2 skill set-up and the sergeants having only 100 proficiencies, 10 strength, 6 agility and 1-1-0-0 skill set-up, far worse than the troops they will have upgraded from. Be warned, as the knights will start with only leather armor, Leather Gloves & leather boots along with a sword & saddle horse - while the sergeants start with only a tabard, hide boots & a Quarter Staff.
