I loved Season 3 for most of the reasons you mentioned zerodix. I realy liked the fact that Anga joined The Lion Guard. I took a liking to her in Season 2.
The new characters were great (Although Binga will take some getting used too). Aside from Rani and The rest of The Night Pride, my favorite new characters are:
Varya: I wish she would not have been just a one off character
Azaad: At First I thought he was unworthy of Fuli, but he then seemed to realize this and stated approaching her from the stand point of. I do not deserve her, but I must try and win her heart.
Chuluun: She is just the best (Lion Guard Exclusive) Villainess the show has ever had. I'm surprised that there were not any romantic sparks between Makucha and She, Although A Leopard and A Snow Leopard would be a cross species parring wouldn't it?
Lumba-Lumba: was very cute
One thing that puzzled me: Were Surak and Nirmala Mates? There is no indication of it, but it would make total since if they were.
One thing I really loved was: Kion and Jasiri's hug.
The Last Episode Wow! I had been waiting 22 years for anything post Lion King 2. I got an entire episode
I had wanted something special for Vitani (Yes because I love her, but also...)because of how instrumental she was in ending the battle Between Simba's Pride and The Outsiders. (If Vitani had not defected then the rest of The Outsiders in all likelihood would not have either). I had wanted her to end up with Kion, but when Rani was announced I figured that ship was Sunk. Being Leader of The Lion Guard is a prestigious position that suits her perfectly. Also having a group of former Outsider as The Lion Guard not only helps to make the former Outsiders feel accepted as members of Simba's Pride, but it also gains the trust of the other Pride Landers.
Vitani's Lion Guard could be interesting characters if they were to get more screen time and character development.
The Challenge of The Lion Guards was very good the only problem I had was with the way Beshte lost.
As for the ending The only thing that would have made it better is if Kion had been aged up just a but more I would have like to see him with at least the beginning of a full mane. smaller that Kovu's but obvious what it will grow into.
Now obviously for Kion And Rani to be Married They have to be old enough. As Simba,Nala, and Surak had no objections to the union. This also proves to me the theory that The animals in The Lion King Universes age at a human rate. Therefore the youngest Kion And Rani could be is 18.