Actually the art made it better. I mean it still sucked to see that window pop up but I would take like 15 seconds to look at the picture. Do you know why they didn't have you paint the events like when you get to decide the fate of someone? Like when I chose to crucify a noble trying to scam a family member and all I got was words and no video or a picture.
Seriously though I made a campaign with cheat mods on just so I could hunt down all the artwork for Rome.
Wow, you made my day with this comment! It's great to know that there are people like you who take time to look at the pictures, I assumed most players would just read the text and move on
As to deciding how the pics were used in the game, I have no idea about that, so I can't answer your question, sorry. I was playing the other day and it seems like you don't get the picture when you make a decision, but there is one when the game shows you the outcome of that decision (at least in this particular case, I had to decide whether to punish, kill or let go someone who committed some sort of crime).
As for hunting the artwork down, I have to say I'm flattered. You'll find lots of them here, in my gallery without having to look for them in the game, the ones I was most happy with, anyway.