Posted: 10/03/2016 at 17:21
5th picture - I think I would keep it as a gravel garden, but plant it with grasses through the membrane. I would also trim any small twigs that are very low down on the plant that's already there to tidy it up and remove the weeds. I did this for the front garden of my former brother in law and it did look good.
4th picture - if the slab is loose I would put it in the middle of the gravel and get a large plastic terracotta looking pot to stand on it and either put in a standard plant or seasonal bedding that you can change through the year.
3rd picture - coloured slate or gravel on the ground, maybe a coloured pot standing just proud of the alleyway, or painted trellis on your wall only.
1st and 2nd pics - as you have some circles already, you could have a small circular lawn or curved beds.
Sorry for the reverse order.