score:2
No markings on the road, no level difference, no signs on the corner means it is an equal crossing and the rule 'right first' holds.
The actual surface of the road makes no difference in this, tarmac and road bricks are both 'normal' road surfaces in build up areas as well as the countryside.
Newer road designs are such that this kind of crossing will mostly have the same kind of surface but the road surface is more based on the use of the road, less on the status.
The sign in your photo is indeed just a warning. Likely because there are two 'roads' so close together.
In T junctions, the rule 'right first' still holds. As it does on other odd crossings as long as there are no special rules for the crossings or one of the roads.
What does make a difference is the level of the roads.
If the road surface is raised to the level of the side walk (pavement for some) the car or bike that has to cross that raised bit to reach the crossing has to give way.
And in combination with signs, there will often be lines on the roads as well as triangles called sharks teeth.
When you face the tips of the triangles, you have to give way to all traffic on the road you are going to cross.
This is Dutch Wikipedia page about Haaientanden/sharks teeth with a good picture.
In some cases there is a different road surface to indicate a different status for the roads, but always in combination with other signs. Most of those areas are 'walking only' or 'cars welcome with restrictions' and the road surface will be very rough, mostly stone.