As in various projects requiring optimisation in specific direction or something?

no, it is only to stretch yourself and try different solutions. When you complete the game, you also get ability to see which quartile you are in (even more info!) so you can see exactly how well others have been to compare yourself with.

The game itself is quite easy to complete, the challenge (for yourself) is in the optimisation and how far you want to go.

But then there is the bonus tasks... that something else entirely...

Maybe a concensus among players could be to allow weighs to gold+time+area such as x1 x2 x4 to decide what is the more costly solution.