Game Idea: "Useful Machineries"

Wondered what you think about this game idea. There isn't a real theme (maybe it will end up as a game about world trade in 16th century..), it's the first time the idea came out from the mechanics.

The players represent some kind of 'inventors', trying to develop and build some industrial machineries used by all the players to get some kind of 'materials' in some other. The core idea is that you score points if other players find what you're building useful for their scopes. A bit vague, don't you think ;-)?

Try to follow me... The course of play is divided in "ages". Each age is made up of 5 rounds. At the start of each age a "Demand" card is drawn, that shows the kind of Materials that players will have to produce in that age in order to score points. There are four kinds of Materials: for simplicity Reds, Yellows, Blues, Greens.

Then the game starts. In each of the five rounds a player can choose one of the following actions:
- Draw some Material chits from a bag, where chits of every kind are mixed. In each turn the player can draw one chit more than the chits drawn in the round before. That is, if a player draws material in the first three rounds, he'll end up with 1+2+3=6 Materials.
- Draw a Machinery card. A Machinery card allows, when put in play, one kind of transformation from a kind or a number of Material to another one, with an input and an output. For example: "Input: Red / Output: Blue"; "Input: 2 Red / Output: 1 Yellow + 1 Green", "Input: 1 Yellow / Output: 2 Yellows"; and so on...
- Put a Machinery in play, made up of one or more Machinery cards. For example, if I've got the right cards in my hand, I can build a Machinery that with an Input of 1 Red, gives an output of 2 Blues and 2 Yellows. Not bad. The player that builds a Machinery is considered his "Inventor".
- Add a Machinery card at the end of an existing Machinery, not becoming inventor of anything.
- Use an existing Machinery, putting in it one ore more of the required Materials, and getting the resulting output.

At the end of each age, each player scores as many points as the Materials created of the kind required by the Demand card (that Materials are discarded), AND the points scored by the Materials introduced by other players into the Machineries invented by the player (1 Material = 1 point).

A rule could be added, so that the players have to produce a certain number of Materials in each age (increasing?), in order to score any points: if all players put their Materials in my Machinery, but i'm not able to produce 5 Reds in this age, I won't score any points at all. That's the risk to spend every effort in research and development ;-).

Well, i've been a bit long and my english, as you've probably noticed, is not that of a mothertongue... So let's stop, and please tell me what you think!

Paolo[/list]