Does your game ever feel small?

[Evil Yoshi Toes]

In the case of a fan made game being worked on by one person it's probably better to think about a smaller scale game. Super Mario World and Super Mario Bros 3 had big development teams behind them and still probably took a long time to make. As far as I know your game only has you, so if you were to create a game as big as those ones it'd take very long. If this is your passion project and you don't mind spending a very long time on it then you can definitely do it, but if you think you might burn out working on it for so long - which happens a lot with fan game developers - then I'd say just think on a smaller scale and make a short game that you can be proud of in terms of quality.

Also, I don't know about other people but when I download a fan game I'm not looking for something huge. I'm usually just looking for something I can finish in a few sittings that does things Nintendo probably wouldn't do with its gameplay and/or characters. Sacred Bells is the longest fan game I've gotten through, and from what I remember it was not as long as SMB3 or SMW. Don't feel pressured to make a really long game. As long as you have something unique and fun to play you should be good.