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

@ Luke Buckle yep that’s the one. Has 1000w/200w switchable. I just put an oil heater in there 2 days ago to trial and room was toasty in under 5mibs WITH A non instant oil heater so a fan type wouldn’t take long. Also consider the heat lamps are 250w so 1000w total if all 4 are on. They feel like they are frying your head off from above when blazing all 4 lamps so depends on what “feel” you want also. As someone mentioned, let alone the cost of lamp replacement. Having been in lighting industry they wouldn’t last super long either (perhaps newer ultra violet do but their also pricier again)... I’m no better either!

Amanda you have a number of options depending on how much you want to spend: 1) Sell them on ebay and use the money to offset some of the substantial cost of new doors. They were quite expensive doors when new so somebody on a tight budget would love to use them. 2) Reglaze them all in a glass that you do like. Bevelled edge glass looks stunning in French doors, but it is really expensive. Reglazing them is a long term option as it is labour intensive with 10 panes of glass per door, so is expensive, and would probably cost more than getting new doors installed. Although clear glazing reduces visual privacy between rooms. 3) Paint them all, to conceal the glass, so they look like a panelled door. This will destroy the resale value, so when you do replace them all you will need to chuck them in all in a skip. 4) Check that the milkiness of the glass is actually in the glass, and not an applied obscure film. If it is applied then remove the privacy film and clean. 5) Get a craftsman to apply a layer of plywood to both sides to cover the whole door so they look like generic, flush panel doors, then repaint. You will need new door handles if you do this as the new doors will be thicker, and your existing door furniture won't cope. I actually don't mind them too much and I have a few similar ones on my own place. They are great for borrowing light from adjacent rooms, but maintaining privacy. If I were you I would live with them for a while before you decide to do anything drastic and irreversible. Best of luck Dr Retro of Dr Retro House Calls

Yip Yah, if you can alter the cabinetry. If all those sections and probably not the bookcase are narrowed to make a gap of 12-15cm, you can have an S-Fold track attached to the ceiling and the sheer curtains will go into the space when necessary. They may pop out a bit, but that will add to the scheme. It is difficult to assess the design scale of those sheers S-fold or Wave track - I usually use white tracks so they disappear and there is one that is only 1cm deep. This is a new way to install roller blinds, which will be hidden. This is more classic in fabric choice, but imagine that the blinds in your situation sit from the ceiling to just below the blocked-in section above the doors - depending on how the doors open. In some instances part of the door stack sits inside, this will mean the blinds will sit about 1cm above - but I prefer to cover all the horizontal lines if possible for a simpler scheme.