You can generate the RDL however you want, it is just an XML file. But you will only be able to run the report locally. To run on the server you would need to deploy the report first, as the server does not run the RDL files directly.
I suppose this is still possible, but it would be pretty slow, and the report would not appear in the report manager or anything before hand.
However, your probably making this problem more complicated than it needs to be. I have work on projects where we generated the RDL and deployed daily with a custom application, and it is almost always not worth it. There is usually a better way.
You can set almost all the parameters of the chart using expressions. The only thing that can't be set is the chart type, but there are ways to get around that as well. Like having all the chart types you need created on the page, but making all except the one you want visible.