Cullen's romance doesn't make him appear as a jerk, he's a rather light hearted character and such a sweet, prince charming LI.
Iron Bull is pretty OK. Somewhere down the road of his romance he admits his true feelings and he changes his entire view on how they work, I think, since he stays committed and loyal to the Inquisitor. He definitely isn't a jerk.
And tbf, I didn't think Blackwall was much of a jerk, a well mannered gentleman in my opinion just with a dark secret, and even though he hid who he truly was he spoke up and tried to make amends for his crime. He helped the Inquisition, put his life on the line for Thedas when he didn't have to. EDIT: even though he f*cked and ducked, I guess I can see how that makes him a jerk, but if it wasn't for him turning himself in I think he would have stayed, and after the INQ., takes him back (if she does) he is obviously willing to pick up the relationship again, he just felt incredibly guilty.
I LOVED THE SOLAS ROMANCE THOUGH! Omfg. It was so amazing even though he crushed the Inquisitors heart, I love those bitter-sweet romances. Solas is definitely a romantic. A hand-holder (aw). His obsession with the Fade was a bit iffy, though. Got old and annoying after a while and in order to keep him on good terms with your PC you have to talk nicely about the Fade with him, otherwise he is a major SOB.
I lost track of the topic accidentally.. 
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TL;DR:
Cullen and Iron Bull are not jerks, unless you classify Iron Bull as a jerk because of the BDSM. I don't really think any of them were jerks honestly, but to be safe than sorry, Cullen, Iron Bull, Dorian and Sera(maybe) are not really jerks.
I wanted Michel de Chevin to be an LI, my LI, don't care if he plays a small part, like dzaqmnxsaixnh. idek whyyy (off topic again heheh)