That is going to be a lucky hammy that moves in there

I agree with the suggestions made above, particularly about freezing food for a week - pantry moths can be a real pain. Apparently most pet foods contain moth eggs which aren't visible to the naked eye. They are not harmful, and stay dormant, but in particularly warm weather, they can hatch out.
It can be a bit of a fiddle getting the last few bits and pieces in place and I'm sure it will have a lot more cover once you have sprays in as well

. Personally, I would add a platform at the opposite end to the house - but that is a fairly major purchase, and the legs need to be long enough so it sits above the 10" of substrate. A platform gives them somewhere else to go and it's a good place to put ceramic items on, like the food bowl, so it doesn't and other bits and pieces like a chew or another small hide. It also gives them some shelter - something to sit under. It would need to have 12" (30cm) legs if you have 10" of substrate. The other items would then be more squished together beyond the platform so the cage would be more full looking anyway

. It's not easy to find them with long enough legs. Amazon has this one with 9.4" legs - you could maybe have the substrate a bit lower at that end so there's a gap under the platform. Or if you're ok with diy, it's just a case of a piece of wood and 4 thick dowels, drilling a hole through the top of the wood and in the top of the dowels and putting screws through so the screws are flush with the top.
Birch platform click here
If a platform seems too much hassle, then a large cork log, like Beryl mentioned, would also give overhead cover, something to climb over and a tunnel to run through. I use both. And have the cork log pushed partly under the platform, so it also makes a ramp up to the platform.
These are just suggestions though, so feel free to ignore! Just adding another hide or two can do just as well (cardboard hides are fine - a tissue box eg).
I am interested to know what the sort of fence is round the back