Choosing external finishes
The planners usually want to see new homes built within the style of the local vernacular. However, this does not mean to say that your home needs to be an identikit and there is always scope to do something slightly different. Homes designed with architectural merit can get planning permission; usually what is required is some allusion to the local vernacular. A planning consultant will be of help if you have any doubts/concerns.
From a purely practical point of view there have been great advances in the materials that can be applied to the exterior of your new home. Even traditional render has seen significant development with modern rendering systems providing superior water protection and breathability in comparison to traditional products such as sand and cement.