It's an interesting and good start. As for having to much forest/jungle, well that kind of depends on the climate you are planning. If its a sub-tropic/tropical rain forest idea then I don't think its to much.
As for the wastelands, not really sure. Some of the folks here are well-versed on the whole climate/geography stuff, so I'm sure one of them will give you some insight for that.
Do some experimenting and post the results, let us comment/give feedback.
Looking forward to see where you take this.