Patio project

As long as you don't have issues with water supply pave the whole area and include a gully leading to one of those buried tanks specially for dog waste.
Just hose the area down regularly and train your dog so his dirty area is next to the gully.

I have timber decking on the other side of the rear garden and need to keep up with the creosote

I hope you have reported your supply of creosote for disposal jim
If you want better and longer lasting staining from your creosote mix it with used engine oil (which must of course be disposed of with the same people who must dispose of your creosote).