Unemployment isn’t endless, isn’t 100% of your pay, and doesn’t allow you to take other work. It’s still always financially better to go back to work. This is exactly the bullshit conservative argument against having unemployment at all, “it makes workers not want to work”.
And yes, more monetary support for striking workers would increase worker power, I already said that. It wouldn’t necessarily cause long strikes, but it would make employers unlikely to be able to starve out a strike. That’s a good thing. Corporate/worker power is so amazingly out-of-balance that strikers are basically always in the right. Maybe with more power they could eventually get to the point where it would be abused, but currently anything that biases things towards workers is good.