Uneven Courtyard Conrete and Pathway- what to do ?

I have a pathway (approx 2m*13m=26SqM) and courtyard (approx 6m*4m=24SqM) made of concrete. The pathway runs along the side of the unit and then opens up to the courtyard at the end of the unit. Unfortunately the courtyard has large slabs of concrete that have partially sunk/dipped due to soil erosion underneath (maybe caused by a tree or maybe due to water run off underneath the concrete) causing the conrete to become uneven. In the centre of the courtyard is the remains of a Hills Hoist that was cut off at the base and removed. The courtyard is an eyesore. The pathway is much better and doesn't seem to have any soil erosion underneath it, although there is some uneven concrete.

I bought some Granitic sand in the hope of covering up the uneven concrete and placing a few concrete pavers on top as stepping stones. However, a builder I spoke to said this was a dumb idea as the Granitic sand would turn to mud in winter and all people would do is end up bringing sand into the unit and ruining the floorboards and tiled areas.

I thought about putting River pebbles over the Granitic sand but was told that River pebbles are crappy if you are going to use the couryard for an outdoor funiture setting.

I am interested in hearing people suggestions as to what they would do and the approximate costs.

Cheers

Flynn