You probably don't need to turn over the soil--probably shouldn't on a steep slope. Talk with your local experts about the best way to convert your paddock. Maybe there are enough native wildflowers growing in there that you could manage by not mowing. Here in the US Midwest we often solarize the soil by covering it with clear plastic sealed all around--this takes a full summer. I have also killed grass by covering it with a tarp for a whole year. For paths I have just laid newspaper, wetted it, and then covered it with mulch. So, it really depends on how big the area is that you are considering. Do find an expert on your area.

Hi definitely remove the x bars on the deck balustrade. Landscape close to the house so it grounds the house. Trees will make it look less bare. Chose some that work for your area, that are evergreen, and are not going to grow really big. With a really plain house - dark colors will make it look better. Dark Grey, or black with a warm tone so it doesn't have a blue undertone in it. Make sure it is a warm grey or black. Use green foliage around it. Paint out the pergola in the dark grey too or white if you want a different look. Fill in the balustrade where the x is removed with plants in front of those areas. Grow a vine up the pergola that is nice.

We solve this issue with our clients all of the time with outdoor water features. We recommend getting a water wall that is suitable for both indoor and outdoor use. Not only will they drown out the noise but will also act as a nice privacy wall. https://www.soothingwalls.com/outdoor-fountains/glass-outdoor-fountains.html

With any post war house built in the 50's the connection from in to out is non existent. Depending on where living rooms are located i would take some of the fantastic windows out and replace them with French doors, or bi folding doors and connect the house to the site. The colour scheme from Karen is perfect to lift the kerb appeal and give it a modern twist. With land costing more than houses these days and the fact that you seem to have quite a big block, after looking at paint colours, opening up the living dining kitchen areas to the outside with a roofed area. Even combining a flat roofed carport which will widen the house to the street making it seem a bigger house, can carry the new look with say an enclosed section for garden equipment, to the opposite side to the house, and if you are lucky enough to have that near the living area it can be used as both car cover and outdoor living. I always think a good landscape architect is worth their weight in gold, to give you a landscape plan, to suit the soil type, your skills level and your preference in planting. Divide up the exterior space to provide outdoor rooms under a tree, paths that lead to some special spot for kids, maybe even a veggie patch with a chock run, and make sure that you use the entire yard, front and back by enclosing part of the front yard in fencing which suits the style of the house, while providing some planting to the street. If allowed a gate structure to blend in with the house, a dedicated pathway with planting each side to the front door, fantastic fencing and consider natural materials like a hand laid stone fence with timber or powder-coated aluminium inserts, to give this house an entry, not sure where the front door is now, so that is not a good look. Gardens always enhance a house, they are never a wasted effort, and if you are not gardeners, make sure the landscape architect knows that and he will be able to select low maintenance plants. All the paint in the world will not give the desired effort that the garden will do to that paint work.