@Artemis_Dreamer I will just give you my personal opinion and leave out the things @Cbear13 already mentioned. Though I have to say, I think of flowers sticking through rocks as them growing through cracks. And I checked the tree, there was a tiny winy small gap between it and the wall in my game.
http://i.imgur.com/KJ8Z5mU.png
What I noticed with MOO off was that some of your columns disappeared. If you use MOO to place objects near columns make sure to place the column last or it will disappear.
http://i.imgur.com/9WCBw6M.jpg
And like Cbear13 already said, objects will drop to the ground, if not placed in a room. Use a room in the basement to avoid that, watch my
video, if you wish to know how to use it. But since this is a wall object, all you need is a wall in the basement. Place it on the wall and raise it.
http://i.imgur.com/4HJBYeT.jpg
I have to admit, this one puzzled me. What were you trying to do? Are you planning to add a door under the arch or was the bench supposed to be there?
http://i.imgur.com/uv7ehPq.jpg
I suppose you used the harvestable trees from debug. I noticed that I can only harvest them, take a cutting, take a microscope sample and talk to them. On the good side that means they wont die, but on the bad side I can't improve their quality. I suggest that you either place their fruits and have a Sim plant them or you create a room with all plants and save it to your libary. All you need to do then is place the room temporarily on your lot and move the plant to wherever you want it. I do that with a room full of plants with perfect quality.
http://i.imgur.com/cvmSxc0.jpg
Another thing I did notice, was that you didn't really use ALT during your item placement. You might want to play around with it. It will let you place items whereever you want them without them snapping to default positions. It can be used to turn around items freely. This is really useful for landscaping, as it allows you a bit more variation on the placement.
Next I have some before and afters considering terrain paint and some item placement.
I personally find it weird to have the drain for rain start in the middle of the house and not go up all the way to the top. So I added another right above it.
http://i.imgur.com/1MB8w9H.jpg
A path to the trash can made this feel more complete to me. Since the trash can was sticking into the foundation I moved it away. And I moved the plant pots in the middle of the darker terrain.
http://i.imgur.com/BktpT7U.jpg
As I said in my previous post, my Sims weren't able to use the mailbox. So I moved it out of the flowers. Those were moved as well to fit in a bit better with your terrain paint there. The paint itself was adjusted a bit as well, I used the remover on it to make it look more natural.
For the path, I prefer more curved pathes so I let it pass the mailbox.
http://i.imgur.com/RYg3N1j.jpg
Having the terrain paint go all the way to the fence, makes it look more realistic in my eyes.
http://i.imgur.com/cgvk9Qw.jpg
For the last I simply added some flower terrain paint, as well as some brownish right under the flowers. This way it looks far more natural than before.
http://i.imgur.com/rUIhJgK.jpg
