this is a really interesting question! i think where it would matter most for rich to regret something, he doesn't. at least for now. regardless of how he fucks up, he's kinda got this mind set that he's got everything figured out and even if something goes wrong, he will turn around to go his way.
but this also makes it hard for him to ever actually grow or connect to other people. he knows he's kinda stagnating and that he can't really seem to keep anyone around without straight up giving them money, and he doesn't like it, but he isn't willing to understand why that is just yet. i think the day he finally admits to his own failures is the day he'll actually regret a lot of his career, and when he'll become a better and more bearable person for it.

on a more lighthearted note, my favorite character to draw! this one kinda changes depending on whoever im focused on the most at the time- right now i'm really enjoying drawing rich. but if i had to choose one overall outside of rich, it might be a tie between tiosus and lephan? siobis is also very fun, though! but i love drawing all my oc's for the most part.