Hehe, if you are in the creative process of designing a game that procedure is quite usual. Often one idea leads to a remote other. That is why I think no one should be ashamed to input all brainstorm-ideas crossing his mind in the creative concept-phase.
Mario (Jumpman) was born out of limitations too. Mouths, hands, and hair were extremely hard to animate, so he was given a mustache, gloves, and a hat. Also, shirts would have been a hassle, so he was given overalls.
There's some pretty amazing stuff that can be made even with such a limited system. Take the game "Adventure" for instance. That was the inspiration for all non-linear gameplay, and was quite good despite system limitations.