Response to an unknown guest
I'm not sure about Fives talking down Harriet. He had a hard time convincing Rex about the inhibitor chips, and the rest of the clones. And Harriet is incredibly stubborn, I think she would have pushed Vine away if their conversation lasted longer.
I don't think the 501st would keep the charges for RWBY. Sure they might have lied, but it's not really worth locking them away. The execution is a maybe, it depends if they agree on Mantle or not.
I think some of Team RWBY might start to second guess Ruby's choices here. Rex and Fives would have good reason to be pissed, so RWBY might feel guilty that they're helping Mantle. I think Ruby would take the What the Hell hero idea to heart, and feel really guilty.
Response to ARC-5597
You might not like this, but my favorite regeneration was 10. The reason he regenerated was because he did what the Doctor always did: save a life. He could have turned Donna's grandfather away (like he asked the Doctor to), but no. He did what the Doctor always did, what he always did. And his "I don't want to go" is always sad to hear.
My least favorite would probably be 2. It was kind of weird that the Time Lords chose his regeneration even though he wasn't dying. It was kind of a waste.
No, I'm glad 12 kept Clara around. He knew she wouldn't throw the TARDIS keys away under normal circumstances. You know, it's funny how that situation is kind of similar to Salem's (begging the Gods to bring Ozma back).
My favorite companion would probably have to be Clara. She was really funny, loyal, kind, and a good match for the 12th Doctor. I still miss her. As for my least favorite, I would probably have to say Yaz. She doesn't really have much of a story or contribute to the story. Even though there was one episode where she found a dark secret in her past, that was about it. Graham and Ryan contributed more and had a very interesting relationship development. Yaz didn't really do anything.