Terrace boards on paving stones - Which substructure?

Hello everyone,
we have now been living in our own home for about 1.5 years and are very satisfied with everything. We have a beautiful wooden house with solid CLT wooden walls and we feel lucky every day about the great indoor climate, the nice appearance, and the fact that we actually stayed within budget.
There is actually only one thing we don’t like: our terrace. The house is surrounded on (all but one side) by a path made of anthracite-colored paving stones, which lead to terrace areas on two sides (one 4x4 large and one 6.5x2.50 large area). The wide terrace runs directly along the southern gable end of the house. The roof and the exterior walls protrude a bit further. Douglas fir decking boards were laid in this area (about 1.20m). Then there is a step and the stone terrace begins.
Long story short: we don’t like the paving stones and we would like to cover the entire areas with Douglas fir decking, which also fits the house much better. Sure, one could have known and should have thought about it earlier. It just somehow dawned on us (independently of each other) only now that it is the terraces that somehow don’t quite fit yet.

The question now is: would we have to remove the stones, or can the substructure for the terrace also be placed on the stone terrace? In relevant guides, it is recommended to first excavate the soil, then lay gravel or sand with a slight slope, weed membrane, and concrete paving slabs spaced according to the substructure, in order to then fasten it on top and attach the terrace boards afterwards. Could the substructure not also be screwed directly onto the stones? To ensure ventilation of the substructure, one could use adjustable feet or similar. What do you think? I would be happy about your tips. Thanks!

Understood, the substrate is (hopefully) well secured. After 1.5 years, nothing should really settle anymore. This should also be the most cost-effective option. The only disadvantage is, of course, the high construction height, as you will probably end up 10 cm higher.

Since the paving is already done, you can assume that the base has already been prepared so that you don't need to do anything more there. You build a substructure, either using WPC slats or you make it out of wood. The substructure must not lie directly on the paving because of moisture. Either you put terrace pads underneath or you buy terrace shoes, which are a kind of stilts available in all sizes. Before you do all that, you should measure how high the terrace can be so that, for example, you can still open the terrace door. Take some pictures and measure how many centimeters of space there is.