My Nijisanji EN3 opinions:
Enna - She is amazing! She has a huge voice range, consequently is really good at singing, but also the way she is talking is really enjoyable. Will look forward to more from her.
Nina - Bleh, do not like her. She tries the mature woman style like Kronii, but her humour just doesn't match mine at all. And I don't like how she presented herself as someone who only joined because she's too lazy to work. Feels like she only joined because she's such a big Nijisanji Vtuber fan and wanted to meet them lol.
Reimu - Neutral on her, she doesn't seem very interesting but not bad either. I'm curious that she likes horror games the most. Will try some of the horror streams I think to form better opinion.
Millie - She is good. Not as enjoyable to listen to as Enna, but she made a really long high-effort intro video (not by herself though, so no Haachama alternative) that was really funny and her interests all perfectly match with my own. Want to watch some more of her.