Place white porcelain tiles inside.....and a metre outside of the new room I would lay cream rectangle pavers and it will look amazing Get rid of all the trees and just grass and place small hedges around the fence and on one side of the new room I will put a decking the same colour as the bi fold timber trimming in oak will be awesome

You have a large open area that could benefit from a little more zoning starting with the bbq and undercover area. If you could build in the bbq and add some bench seating which overlooks the back yard and add some vertical planters for herbs or succulents to separate this area. Zones create interest and you may enjoy the separation from the play areas while still maintaining supervision. Plants along the fence could certainly be a variety of lilly pilly or what about some citrus trees like limes for the cocktails, lemons for the salad dressing etc? Raised vegie gardens? A feature tree would be nice too but not sure what suits your area. Magnolias are very beautiful and the flowers are divine!

If you can put doors on the whole back area and deck or pave out to a functional size for entertaining - be sure to have as close to same height as inside and the whole width of the house if possible. You could do the pergola which looks gorgeous and makes a cozy feel. On top of the pergola you may be able to do a weatherproof retractable awning if you do not want a permanent covered area. That would make a whole area for indoor outdoor entertaining in all types of weather. You can still have a step down area to grass and plants at the rear. Travetine is great and easy to hose down. You do not have to concrete them down use pavers on a good road base. You would have to speak to the experts about how to get the right height - also be sure to have a slight fall away from the house.

a see through roof above a vines would create a haven for bugs and mildew but, depending on the size of the available space and your local climate why can't you have a covered area closer to the house with a frame around the front and/or sides to support a climbing plant? ...a grape vine can produce fruit and be kept in check with careful pruning but unless you want all that work and a plant that can potentially take over the building there are many alternative climbing plants that can provide leafy shade and autumn colour...something like this?