As the windows are framed individually I would also suggest two separate roman blinds. Set up to the height of the picture rail will accentuate the ceiling height and tie in with the architecture of the room. To have the blinds at this height will also allow you to see through 100% of the window area when the blinds are open. Where these blinds hang to will also be important to consider. I would suggest the base of the two romans be set to the top of the sill, as to set them lower will show the sill extensions on the left and right sides sticking out. All the best!

BASIX is designed to improve the energy savings and comfort of your home so it's much better to include this in the whole design instead of attempting to fix it at the end and you can't apply for building approval without a proper BASIX certificate lodged with the new plans so you need to clarify this issue before the plans are finalised but you can't apply for BASIX certificate without making sure the design satisfies the regs so first be sure you know the exact compass directions for every external window as the BASIX ratings are different for different window directions and you may be able to use various combinations of less or smaller windows, sunscreen glass, double glazed and/or wood or thermal break windows, higher, shorter or narrower windows, verandahs, alfresco roofs, shade sails, pergola, fixed awnings, trees and shrubs as well as external blinds or neighbouring buildings etc etc..(as well as the colour of the roof and the ratings for your lights taps and heaters etc!!) and this can be different for every window but if you are doing your own design you can also DIY the BASIX application and test various options on the BASIX website before you finalise the plans..(eg a smaller horizontal highlight window on one side and narrower full height window on the other with higher rated light fittings and a ceiling fan may be the best combination and, although each window is treated separately it's the total combination of all energy and insulations and flooring and roofs and light fittings, taps, heaters as well as the windows that satisfy the BASIX ratings.... there's no cost to use the BASIX website (until you finalise your passing rate and apply for the certificate which is a relatively small fee) and i've found it very useful for testing lots of different combinations until you have a "passing" rate and are satisfied with the best choices and for modest homes and renovations you can complete the application work yourself to receive the BASIX certificate to add to your Development Application but, an experienced professional designer preparing your plans should be able to advise you how to meet the BASIX requirements and also complete the application...unfortunately a photo won't help unless the sun angles and the whole design are exactly the same as each BASIX is unique to the individual building

I love your view! There's options here, and they'll be led by where your blinds are installed in my opinion. It looks like you might need to install the blinds to the face of the architraves, in which case, I'd be selecting pale blinds to sit outside the window as they'll, hopefully be up out of the way most of the time. If they fit inside the recess, then I'd select dark.

Remove the blinds then look again as it would be closer to a look with a simple blind with no scalloped bottom. Shutters block a lot of the view, whic is great if need the privacy