Please share some estimations about the release date.I wouldn't worry about Eva losing interest in the game or decreasing quality of the updates. The first option is just unimaginable because of the ambitions Eva has for this game that I think are too big for her own good. On technical level, they'll only be better. If you compare Chapter 2 Alpha with Chapter 8 Alpha, then Chapter 8 in the Alpha stage was already proofread and fairly polished, comparable to the state of Chapter 2 Final. If by "piss-poor updates" you mean the content, then this game is structured in such a way, that Eva, even if she wanted to, can't really back down on the content. Each Chapter moves the timeline forward which means plot lines also need to develop at the same time (doesn't mean at the same pace). And because the game has so many different branches and paths, Eva will have to account for all of them in some capacity while writing each update. There's just no way she could release an update with only one or two scenes (like some updates of GGGB were) without having to think about convoluted plot reasons each time the content for a certain romanceable character is not available. You could say that Eva wrote herself into a corner with this one where she HAS TO deliver a big update for each chapter. It's possible that some of the less important routes will be cut short due to sheer amount of them (I struggle testing every path, imagine writing them), but it's impossible to do that for the main characters without causing a massive outrage among patrons.
The only real danger for Eva that you may worry about is the increasing development time. And even that will have its limits. If Eva takes too big breaks, then it will make her writing even harder, because the events won't be fresh on her memory anymore. And I know that both Eva and I are more productive when we take small breaks in-between to recharge, but are still focused on the task at hand. If I have to take a one-month break from something, it's extremely hard to pull myself back into a working mode. The brain gets rusty like that and Eva knows that.
Thank you!