For the past few weeks I've had so many loose ideas pop up with me having no idea what to do with them, or how they'd even fit. And then all of a sudden I get an idea that ties one loose idea with another, implies a few more existing ideas as an effect, and gives yet some more of my earlier ideas a purpose to exist. It's like a giant hole has been filled, and I couldn't think of a better way to tie everything into a theme. Fellow indies, has this ever happened to you?
Of course. This is constant on everyones mind. You have an idea, then you think about it, go back and forth etc. Its part of the process.
Now, what in my opinion I think you should do, is think if this idea is feasible technically and economically. I mean, can you afford to do it? Is it not too big or expensive? Also, can you really do it, or your team? And finally, one that most people forget, is there a market for it? Even if it is tiny you need to think about if you will be able to sell this.
Some ideas are just not right for the time being. As an example, if you told me you had an idea for a zombie game I would just ask you to think about something else because there are just too many zombie games. Unless you really have something unique it will just be one more zombie game in the flood of zombie games.