I’d recommend NOT planting too close to walls. Plants will grow and spread, and could potentially cling to walls causing an ongoing maintenance issue. Roots could also be an issue as they grow. Small plants look nice initially, but can be a menace in the end. Here’s looking at you Buddliah!!! I wouldn’t plant grass that close to the house walls, difficult to keep tidy.
I like the stone/gravel surround idea. Where we are there are suppliers who have a big range of different coloured/shape/size stones.