I just googled & found this site, which quotes cost of R2.5 75mm. there are other suppliers as well. What was quoted to you for cost of roof installation, and was it itemised so you can see exactly what thickness the foil-backed insulation builder will use? I'm guessing the thinner (lower R factor). So, the new quote should reflect a credit for the cost of previous insulation, since it won't be used, then cost of thicker insulation added. Does that make sense? If you are unsure, best to speak with the builder. https://www.pricewiseinsulation.com.au/product/heavy-duty-fletcher-permastop/

What types of metal are available? I am thinking a bronze one with timber blades could work visually. But check specifications first as not all fans are suitable for use in alfresco areas. Dr Retro of Dr Retro House Calls and Dr Retro Virtual Visits

No to terracotta, that would be closer to your gutter guard that doesn’t work with your bricks and would be the first thing I’d address. You could square up the bricks around the garage doors and modernise the front door screen. The roller doors could be more modern too, although they look fine and what they are.

The house pic just shows what can be done -- the base colour is the worlds most boring grey ( in fact , it may be an optical trick due to the materials , but I suspect the 'middle unit' and the terrace walls are a different shade of boring ? ) , the mustard or caramel or whatever you want to call it really sets it off ! The roof is interesting enough to probably even be done in the same mustard -- that would be a Wow moment ! -- but I assume it is still in the silver , which is a good compromise ! If it is silver roofed , I'd like to see the gutters and trim around the roof done in the mustard too -- it only needs to be 60-80mm wide to make a statement ! Personally , I'd also do the support piles in charcoal stain instead of the natural timber , but maybe that's just me .