You should be able to do three panels in those windows up into that arch with horizontal louvers and fully functional. Your shutter maker just needs to line vertical posts up where you have vertical mullions! giving that center shutter something to hinge to. Here are a couple of similar windows I have done. It's a partial arch but it's the same concept with yours

Something to consider with roller blinds- The blockout ones can really block the airflow in Summer, and if you do leave the louvres open, the slightest breeze will cause the bottom rod to bang against the window frame. You can fix them so they don't do this, but again you have the reduced airflow.....which is why you have louvres in the first place. We have the same problem. My son's bedroom. He seems to have adjusted to no window coverings. Luckily we have no privacy issues.

You could go with curtains that run across the whole wall that follow the fall of the ceiling. This would read as one large fabric ‘wall’ rather than two angled ‘slices’ of window making the space seem larger. A double track system with blockout and sheers would stop the hot sun and still allow beautiful softened light in the room and full view with curtains pulled back.

Assuming the front balcony is north facing, and the side window is east. I would do shutters on the French doors and the windows that are either side of the doors. Shutters on the other windows as well. My reasoning is, roller blinds will knock back and forth when the windows are open. If you are sleeping with your windows slightly open for ventilation then this can become annoying. Your home lends itself towards a plantation shutter vibe. You can position the shutters for full sun or partial privacy and everywhere in between or completely closed. Roller blinds are restrictive, they are either open or closed. You could always add sheers or full curtains on the side large window if you wish. The balcony shades the front windows. It really depends on your budget.