You're 100% wrong about Ursa.
Ursa never thought Azula was a monster, and she never treated her that way. That's why Azula's hallucination of her- coming from her OWN subconscious- is telling her that Ursa loved her. The conversation literally goes: "You think I'm a monster" "No, Azula. I love you." Part of the reason Azula has this breakdown is that she's realizing that Ozai didn't value her and that Ursa- the one she spent years resenting- did.
Ursa never even treated Azula like a monster. From what we saw, she cared enough to try to correct Azula's behavior. So your assessment that she didn't do anything was wrong. Nor did she favor Zuko because she had no issues scolding Zuko when he threw bread at the turtle duck (she also doesn't harp on the fact that he got that behavior from Azula). She also made Zuko play with Azula when she asked. Why would she do that if she thought Azula was a monster?
Ursa never treated her that way. Even in the comic panel you brought up, she asks "When did I lose her?" Implying that when Azula was a kid she didn't realize anything was so severe that Azula couldn't be helped
I didn’t mean to imply that Ursa actually thought she was a monster, it’s more so the way Ursa acted made Azula feel like she did(even if she didn’t intend to). I think she saw Azula going down a dark path and being turned into a weapon but had no idea how to help her.
Also not trying to make Ursa out to be a horrible person. I think her having these flaws makes her a more interesting character. Like you can love your kid and still let them down, especially in her situation where her options were limited.
I do think the show gives us a lot of evidence for her bonding easier with Zuko while struggling to connect with Azula. So while it is mostly due to circumstances out of her control she still owes it to her kids to make them feel loved and should acknowledge the ways she may have let Azula down growing up. She even mentions this in The Search when she apologizes for not loving her enough.
(Plus there is the scene of her laughing at Iroh’s letter about seiging Ba Sing Se, which suggests she also held nationalistic views of some kind. The same ones that made Azula who she is. Which adds an interesting angle to her character.
Overall, my biggest gripe was more so trying to imagine how Azula would react to that conversation and how it would confirm all her biggest insecurities and how she keeps talking about losing her but she’s still alive and out there needing help. Again we see with Iroh, who stayed by Zuko’s side and would defend him even when he was a villain, talking about how he is good at heart(even when zuko wasn’t around). Azula doesn’t have someone like that.