Finish an Era with 2000 Prosperity
If we work on the premise that a village of 300 resources is an easy target, then this development asks us to create seven villages of this amount. A tall order? Perhaps, but there are ways to make the ride significantly smoother.
We want to focus on a development not far removed from that of the Fantastic Era development - lots of villages, lots of completed level 1 developments, no big focus on great developments. However we want to add one extra element to this, and that is the element of resource replacement.
As Giants improve so too do their basic abilities. While it's crucial to open up a Giant's aspect powers it is similarly vital to improve their basic abilities as doing so allows the creation of 'great' resources instead of standard ones, allowing for far greater resource creation in a smaller space.
The primary difference, then, is this focus on replacing old resources with new ones after powering up our Giants. Get the Forest Giant a pair of ambassadors (1 forest, 1 any) and then set him on a job replacing all his old plants with new, great versions. Similarly the Rock Giant should unlock his ability and do the same for his minerals. Don't forget your aspects as well.
Doing this can turn a village generating 300 resources into a village generating 400 resources - it's a significant boost, and one that brings the task of generating 2000 prosperity all the closer.