First off, let me mention I've played almost every single MMO since 1997, I've seen what works and what has not. PSO2:NGS will fail harshly if the game releases as is and definitely a lot of issues are needed to be addressed, and I'll try to be as specific as possible with what I've currently seen. What I can honestly gather, is this is heavily pushed into the realms of grouping and solo seems to be an afterthought - bearing in mind though, this is cbt and most likely missing a massive amount of weapons and gear that could make these issues a moot point.
This is something I'm going to add too as I play more classes, so far I've only played Techer to level 9. And the very initial problem was the severe lag, that was fixed pretty quickly though and for a time, NGS was fun and entertaining as explored the new areas then problems started, and I wasn't the only one complaining about these issues.
Slash the HP of all enhanced, dread monsters and bosses by at least 50%. The initial talks of how much HP overworld monsters have wasn't a joke, it gets BORING fast. Spending 30 - 40 minutes killing a veteran Daityl Sword I was seriously thinking if this was a joke, it's a joke right? This isn't difficult content, it's just mindless and boring, there should be no reason why a group of 5 - 8 people should take no more than 10 minutes to kill it, this feels like the content is not scaled period, feels like the content is scaled to 32 people fighting the boss at once, and that will never happen, same with content like the tower having to kill a regular Daityl sword boss is bad enough because its a slog just to get to the boss solo.
You don't need these bosses to have copious amounts of HP when they can instantly kill you went enraged anyway, this just rubs more salt in the wounds, Honestly ~ no joke, reduce the HP of these mobs significantly or make them scale properly to the amount of people fighting them otherwise, nobody is going to waste time fighting these.
Double Jumping and Soaring is annoying, especially in towers/cocoons as it feels really twitchy and annoying when you are trying to reach a golden cube that has been placed in an area with literally zero room for error to reach it, almost like the classic jumping puzzles....just more annoying, many times the soaring would just randomly cancel itself too.
Seriously worried about towers, are they all going to be the same vector style, low/no effort dungeons? That are not scaled for solo players? If so, this is a mistake. NGS needs to have its content vivid, inspired and want the player to delve more into the game, also I couldn't find anyway to leave the tower without logging out, this is a problem for joining a rando party if someone decides to...you know..afk and/or isn't geared enough to really help out.
Class balance, also very worried about balance. PSO2 was extremely unbalanced and everyone knows it, NGS needs to have some effort made to balance out the classes, can't really say much about the balance at the moment since its early days but this has always been a major concern.
The game has ALOT of promise if many of the obvious issues are addressed, the game has the potential to be a lot of fun and be amazing but if nothing is currently done about the worst issues, I can see NGS not doing particular well and losing a good amount of players very quickly as they get bored and move onto something more fun and entertaining.