Very nicely done - utilised similar space in a 1914 Edwardian split into three suites, retaining the character with inset panels on the doors. left an exposed cubby in a space similar to that where the red basket is in your photo here, or the under-stair bar example earlier, lit from above for an unexpected display of glass art. Good to see creative practicality!

Framed corrugated iron shutters left natural would be my preference, colour might be a bit 'try hard' and natural will sit in the environment more easily. Could even make barn doors with it if you prefer that look. The actual barn door fittings are the pricey bits I believe. Our cyclone was made of corrugated iron (by pro shelter builders) and it never ever budged (loud though) so a bit of coastal? wind won't worry it. You don't have much wind going by photo's, all trees seem to be growing upright so a regular build will be fine.

It looks like you have some great wall space. No matter which style or scheme you choose for you living room, you can't go wrong with built-in storage with doors - especially with kids. In our living spaces we have tried to build in storage with adjustable shelving that is big/deep enough to fit those large clear plastic containers with a lid and wheels that you can buy from Bunnings / K Mart. These containers are great for keeping like items together in such as toys, craft/art, sporting gear, blocks/lego, presents/cards/paper. You can bring out a container or two at a time to play and when done throw everything back in and close it behind a door. Once the kids outgrow what's in a container, you can donate/sell/bin the contents and re-use the container for the next thing. On your red wall, you could have a full floor to ceiling cupboard with tall cupboards at both ends for toys etc, tv on the wall in the lower middle, drawers/cupboard underneath for dvds, games and cupboards above the tv for less used items. You could also do something in the same same style/colour on the grey walls to the left including building in a workstation as part of it for craft or as the kids get older if you need more storage. We just have plain white flush doors with nice handles but there are so many great options for colours and styles - including red if you want to keep that wall red. Some Houzz inspiration:

Console table behind lounge would be wonderful, as per Julies photos above. But even at the moment from your photos I think it looks wonderful with the pieces you already have in that space. My suggestion would be to remove the small bookcase, as it is cluttered with random things and doesn’t look good in the space. Replace with a small shoe storage bench. An artwork on the brick wall above your lovely single chair, would break up the dark brick wall. Hang the mirror above the new storage ottoman, if you are able to. If you are not renting.