3 days isn't enough time to assess something. We didn't even have practice mode to properly go over every situation. Give it a month and people will find a way to punish it. If not then discuss changes. I find it funny there were complaints about nrs changing things too fast and now people want more changes before release. Theres no way to tell whether the game will stay the same before launch.
Of course there's not. THAT'S THE POINT! It's a beta so there are likely obvious flaws. This is the time to talk about them, not after it's released.
If someone went into the balancing process before release with the mindset of wait and see for literally everything, which is tantamount to your position, then there would be no balancing process at all. Waiting to see is for the product on delivery. At this stage, you need to talk about whatever even might be suspect. I mean, if we had found option selects that broke offense, say allowing you to make your incredibly negative overhead safe, which results in the character having >50% entirely safe 50/50 mixups, should that not be talked about?
I mean, it definitely might've helped if someone mentioned it before Raiden went live in MK X. Which is just one of many OS's and a few infinites that had to be culled early on because it had no public beta to iron these things out at all. But nah, we should've let that rock until after EVO, definitely.
To reiterate, this is a communicative stage. When the game launches, I'll buckle down, grind, learn all possible counter play, let it marinate for bare minimum a month after I've done all that, and then maybe I'll think about saying X or Y thing is a problem, but until then if I see something potentially problematic, I'm going to talk about it because now is exactly the time to point out any red flags.