Sounds fine.
It doesn't matter about procedural content. You can sell technical features, or enhancements, as much as you can sell hand crafted scenery. You don't have to squeeze yourself into any preconceived molds.
If you can describe whatever you produce as a discreet, identifiable element then people interested in seeing the elements they want can contribute: whether non-refundable, or not, whether advance or pledge.
Okay, I get the idea. In my case the best selling thingie would be additional features or interface upgrades.
Of course, you may prefer to be in control of your own direction, and may desire the freedom to abandon a planned feature on a whim, and work on something completely different.
This is where you have to be careful. Are you just accepting non-refundable patronage from players who express their preferences, but trust you to focus work where you're most enthusiastic and capable? OR are you really in the business of selling features to those who want them and only accepting money (otherwise refunding any already paid) when you deliver the goods?
Yes, I'm afraid of this trap. I DON'T want to sell my soul, but also I'm a person with a strong sense of justice. For example that sense of justice doesn't allow me to just say "DiabloRL is dead folks", despite the fact that working on it doesn't bring me any fun anymore :/.
Here's an example of different motivations behind people who might be willing or inclined to provide you with money:
1) Kindly donors who like what you've done, like what you're doing, but don't mind if you stopped work tomorrow and joined a monastery.
Praise the Lord that such people exist
2) Patrons who expect something for their money, but don't really mind what it is, as long as you produce more of what you're good at.
I would want those to be the majority, but of course I have nothing to say in this regard :/.
3) Customers who'll pay you, but only for what they want (a new feature, bug-fix, version, etc.), and only when/if you deliver it.
For these I think a "pledge" system would be good. Now is the question of how it would work :/.
You don't have to produce any live updating AJAX malarky, nor any data driven PHP.
You could do a weekly diary in your blog and simply itemise who's contributing towards what and how far you've got in terms of delivery. The more meticulous you are, the more money you may get. Sure, you could simply list contributors and say "Ta", but that may not necessarily inspire others.
You mean that "non-automatic" updating of all the statistics would prove enough?
The more you demonstrate how your development and delivery directly relates to contributions, the more likely people are to contribute their coin too.
Remember: money is work. But you don't get money for work automatically, you only get money in exchange if people want your work, and are CONFIDENT that you'll work for the money. That means making bargains (art for money, money for art), or making your work visible in terms of progress and delivery.
* Kornel Kisielewicz feels more and more like he's selling his soul xD. But yes, I do get the idea.
Sure, if you're a pure artist you'll not sully yourself by accepting filthy lucre in commission. You'll only produce what you want and damn your audience, leaving only a hat or bowl on the pavement for purely altruistic donations.
Charity or business. Pure art or commercial art. It's up to you. Nothing wrong with pure art, I'm just trying to provide a perspective on commercial art - specifically, copyleft art.
Sometimes I feel that unfortunately I might be a unconvertible "pure" artist (if an artist at all). On the other hand I understand, that I wont be able to produce the quality of art I want to achieve if I don't "sell myself" a little. It's a question of Sacrifice(*)
(*) and in a few years, maybe you'll all see this is a pun
Developer
