I'm feeling so uninspired at the moment. And it feels so big and confusing and I don't even know where to start.

Oh, I hate that. I'm sorry you're having to go through it.

My recommendation would be, as you said, put your head down and get to it. Even if it's not the best thing since sliced bread, it'll give the beta something to look at. And you can't fix a blank page.

*fingers crossed* for some inspiration and motivation