Based on some ideas around, found a method to do remesh (in this case is more like a poly reducer), converting a high-res model in a subdivision surface type of model with much lower poly count than the original, and which can be Subdivided again. Not a real Remesh since the mesh is not as clean as a Remesh method, but gives pretty nice results.
The guide for the method, and a script from Brecht that is needed in one of the steps, can be downloaded here.
The guide alone can be found here.
I guess those steps would be just one click on a button with a macro in 2.5.
For those who don’t know what a real Remesh does, here is an example.