There's some long standing Profession/Trait weaknesses in Sovereign creation;

Adventurer Profession; No sane person would ever pick this as there's no real benefit from starting at level 2 compared to other Professions that give much greater long-term gains.

Bandit Lord; The only advantage gained from this is on very small maps where you might be able to get a jumpstart against another nearby sovereign.  The 2 Bandit units supplied are so underpowered as to be laughable.  I would propose that those units grow a body for each level gained.  This gives the units better legs during the early game.  Also give the Sovereign the ability to charm Bandits (similar to Beastlord)

Warlord; The ability doesn't seem bad, but seems more appropriate for an Accountant/Miser than a Warlord.

Natural Leader; Should reduce cost by half.  Free has been overpowered in the games I've tested.  You could take this (as it is now in game) with the Cruel disadvantage for a free +1 to Attack

Might; +3 Attack is okay, but not compelling.  I would also add +5 to Weight Capacity

Equipment; It would be nice to have more options here.

Editing your Sovereign/Faction; Currently no way to edit either.  Really wish this was doable as it would be much more convenient than having to recreate either from scratch when all you probably want to do is a small tweak.

Side note on Faction creation; cycling between races there's no way to tell the benefits of each race unless you already know heading in.