Howdy Ceri,
Thanks so much for your comment... it means a lot to us as first-time devs!
It's awesome to hear that you've been excited for this project from the get-go. We really appreciate your initial thoughts.
Some answers:
1. We will definitely be adding more options to the menu. There will be a quit button at the very least (hilarious oversight only realized after assembling the demo), and our programmer is hoping to set up a CG gallery along with a configuration menu. We will be releasing a guide to completing all the endings alongside the full release, though it may be as a separate download.
2. We've actually been considering making some changes to the title screen and menu to make them more dark and ominous. The fact that you bring this up strengthens the case! We appreciate the suggestion, and will definitely take it to heart.
3. There are six bad ends and one true end.
4. The full release will be free with an option to donate.
Thanks again for providing us your first impressions! It's wonderful to get feedback, and extremely helpful in bringing the full release to fruition -- and any future releases we might have. When the time comes, we look forward to hearing what you think of the full release! Cheers!