Hi, We also break up a long hallway with zones, and often do it with the ceiling and shallow nib walls / feature recesses. You have the width to do a few things. When the hallway is straight we create short length dropped bulkheads and 'frame' areas that lead into specific locations... eg the entry can have a small dropped bulkhead at the end of it that feeds into a feature protruding wall combined with a different ceiling height. That wall might sit out by a couple of hundred mm and that allows anything from a series of recessed boxes (shelf like) to a feature frame for large artwork. We also change ceiling heights through sections to zone off eg the living end vs the bedroom end or place features such as light wells in them. Cheers

When you're looking to integrate a contemporary look within a period context, it's important to respect the integrity of the architecture - lighting pieces that marry old and new are the way to go. My favourite pendant in these settings would have to be the Jasper Morrison designed Glo Ball by FLOS. It is a classic piece that will stand the test of time and works well in both contemporary and period spaces. Here is one of my projects that includes the light in a contemporary home- Here is an image I've found (this is a project by NEXUS design), that displays the light in a more traditional setting-

I have high ceilings downstairs 2.7m and std door and window height and looks fine but do have wider front door 870mm don't like tall and skinny doors. Having said that on one wall do have higher windows and they look fantastic but that was to catch sun and block out ugly neighbour house so std window size just fitted higher but look so good in my downstairs open plan area could have gone larger height windows all around but don't have verandah across front house that would look odd with higher windows and no light benefit and more heat n cold thru glazing. Good luck with your decisions

Judging by the plan, the photos and your comments it appears that too much heat is coming in from high light glazing (clerestory windows) into the lounge and dining areas. Both rooms will be cold in winter because the direct heat from these windows is not enough and not absorbed in an thermal mass and they do not have ground level windows or glazed doors facing north. The elevated floor means that it is cold under the house so heating in winter goes down as well as up. The roof would lack adequate insulation due to the period in which the house was built. The roof tiles probably have another 15 years maybe a bit more so it is costly to insulate from the top (i.e. taking roof tiles off adding insulation then putting roof tiles back in again. The colour of them is contributing a lot to the heat. So what to do. - add external shading device to the highlight glazing, maybe timber battens 40 x 40 at 20mm spacings. This will block direct sunlight within the shading season. That helps to reduce heat intact and see how you go. If that does not work then - add a rigid foam core board to the underside of the timber ceiling, e.g. Foilboard which is 20mm thick r 2, then install a 12mm plywood ceiling lining under this. That way you retain the timber rafter ceilings but also one that has a light coloured (hoop pine ply) timber in between. (Note this is costly) - big gains in heat loss is achieved with underfloor insulation. Try r3 bulk squeezed tightly between the floor joists. Then you can plan for the future with the following - change glass in windows and glazed doors to a low e glass - install insulation into the cavity of the external walls using a company called envirowall. - replace roof tiles with a light coloured metal roof, replace the existing roof battens with a 100 x 40 batten so that you can install a 100mm thick anticon insulation. All of the above costs money and if you don't do it then it costs money to burn energy to keep the living rooms between 21 to 27 degrees year round (what we consider comfortable) so if it tough to decide what to do or not. As an alternative For about 40k you could spend 30 of it on solar cells, and an awesome battery (Tesla powerwall 2) and buy some wall mounted ac units. But that would be kicking the can down the road. But sometimes you have no choice. Good luck