All very good points - especially as you're mainly just one person. The important thing is reaching a finalised version containing the content from the base game itself. And having completed it, I know how much work you have ahead. Especially weird stuff like items and NPCs that I could never find the use for. There's a lot of stuff / rooms / screens, and lots of enemies which are only damaged by specific weapons.
Anyway, you have my moral support. Honestly I'd pay some money for the final version, but that throws up legal dangers with Nintendo. The original game sells for between £600 and £1500 on eBay now. So your project is important in more ways than one.
Have fun with it. I'll keep an eye on the page. :D