Haven't had any issues at all roleplaying my character the way I wanted to despite the ability checks and the urge constantly mentally nagging the character, in fact it was quite interesting... but what ruined the character for me was a particularly unavoidable shoehorned scripted Long Rest where;
the character decides to brutalize a well-loved NPC and permanently delete them from the game without any of my choices mattering.
.
You could send her away you know, knowing who you are, and what you are capable of.
I personally loved that outcome. If anything decades of playing P&P RPGs taught me, is that you are never in control of the game. Nor meant to.
It's never about power fantasy. Shit happens, and you have to learn to deal with it... because ROLEPLAY. You picked a ROLE of Dark Urge, you have PLAY that role.