It's about time we got a new trailer for this, I was just thinking yesterday about how it comes out next month and don't know anything past the first trailer.
That being said, it seems that there isn't all that much that we've been missing out on. This game seems very similar to Mario Tennis Aces in many respects, and while that game had great core gameplay, the content was underwhelming. The only new mode that was shown in this trailer was Battle Golf, and while it definitely looks interesting, the single player aspect seems to be severely lacking.
Aces mainly focused on playing online, and Super Rush seems to be following course. While that's fine, I don't think that the slow paced nature of Golf suits it quite as well. Obviously the new Speed Golf mode is set to change how the game works to make online multiplayer much more interesting, but I doubt that it's going be quite as addictive, or quite frankly, fun.
Golf games generally are at their best when you take the time to line up a decent shot and then see that effort pay off in the results. Nothing quite beats the disappointment of barely missing the hole or excitement of a flag shot. This game doesn't seem to have any substantial modes for this more traditional style of Mario golf, such as tournaments, which is by far the thing that I'm most concerned about. Maybe we just haven't seen it yet, but it's not looking good. I'll still play it a ton I'm sure, I was just hoping for a little more.
Oh also characters are kinda random I guess but I'm sure that they'll pull another Aces and add more characters via updates. Courses still look sorta off but the Mario enemies and stuff make up for it a bit. Story mode looks kinda boring tbh, it'll probably be three hours long with little variety and super easy like Aces.
Yikes, if I'm going to go to this amount of effort in writing my opinions on a game like this maybe I should start writing for the shroom again haha.