Completely agree about the sweep after a shield bash. Though I find comboing the sweep after a headbutt to be similarly useless. Too much stamina drain, and it will knock your target back so far you can't follow up with anything other than that pouncing top light attack. Just not worth it.
About the only time I find the sweep reasonably useful is as a chain finisher. Heavy / light, light, sweep, side heavy will connect, and is the only way I've found to combo a couple heavy attacks.
Been trying to take advantage of that dodge block bleed, but the timing on that feels all over the place. The dodge has to be late enough for the block to hit, you have to be close, and the timing is strict enough after a successful block that I'm not sure you can reasonably hit confirm it. Which of course means if your dodge was early, or you aren't in range, you are left swinging a heavy attack with your pants down.
I want to love the Valkyrie... I love the aesthetic, I've always enjoyed spears and shields in the few games that include them, but damn, she feels like she has a lot of tricks but no way to capitalize on them.
Maybe people will figure out something new tomorrow. Only day one after all, can't write off a character that quickly!