I have a lot of faith in the creator of BGaE 2. He knows his stuff when it comes to making games. He made Rayman 1 and 2, which are very good games. And of course the original BGaE and the newer Rayman Origins and Legends. He's been waiting a long time to get the right opportunity to make a good sequel to BGaE 1. And I'll admit, I never got far into it, but I really liked the first game. It's sad that they ditched the characters, but the way I see it, the new characters will probably be fine as long as Ancel and his team take their time and give it the attention it needs.
I mean, Metal Gear Solid 3 had an all new cast of characters from the originals, while sticking to the same universe, and it did just fine.
As for the online gameplay. It doesn't look like playing with friends will become a focus. It's really hard to tell at this stage, but I am hoping it's more of a shared world deal, where you can play with friends or just ignore people and go about your adventures alone without worrying about intrusions into the core adventure and story experiences.
I just hope it isn't going to have any competitive aspects. And if it does, they should be opt-in only.