I hate wood blinds so I am not much help I have a 50s ranch and use solar shades for light and heat control but I get to enjoy my view and at night for privacy I have drapes I just find wood blinds or shutters make my space feel dark and I hate not seeing out my windows

Thanks for your comment. I'm not totally sold on wood blinds. But whatever type of window treatments I go with, the preference is to have them mounted inside the window frame.

I wonder if it would be practical and worthwhile to have the quarter round molding (that I've shown in the photos above) removed from the inside of the window frame to gain more depth? The depth would go from 1 to 2 inches, so I would gain would gain an inch. Just not sure what to do about the gap that the quarter-round is obviously hiding.

I would remove a piece of the quarter round to see what kind of gap you are dealing with. It’s not hard to do.

If the gap isn’t too big, it might be possible to fill it in with caulk.

Removing the quarter round molding seems like a solution to gaining more depth. But after looking at it more closely (see pic # 3) the vertical molding between the panes actually butts up against the quarter round at the top. So there would be a gap at the top where the quarter round was removed. However I believe the gap would probably be well hidden by the headrail.

I haven't done it yet but it kind of seems like removing the quarter round could open up a can of worms/problems. Be just my luck something would get damaged and I'd end up calling a window installer for repair.

And here's another thing, if we did go with the 2 in. faux wood blinds, even with the added inch of depth gained by removing the quarter round, they still won't be flush and with the window opening. And it looks like most of the blinds have a minim inside depth requirement of 3/4 of an inch. So now I'm thinking what's the point of removing the quarter round?

Removing the quarter round will not be easy and like you said, could cause damage. Faux Wood blinds will be so heavy you will have to have someone pull the string and another person lift the blinds to get them up. There is not enough room anyway, even with the quarter round removed. Curtains or the cellular blinds would be easier.

Actually from some of the mounting instructions I've been reading, there is enough room. According to this Window FAQ from Blinds.com 3/4 of an inch is the minimum inside mount depth and I have a full inch without removing the quarter round. They just won't be fully recessed.

But you're correct that the weight may be an issue and was the main concern of one of the sales agents I had to my house. They said that because there's only an inch of depth that there'd only be enough for one or two screws in each bracket (on the blinds they sell) and with the window being so large, the blinds will have a lot of weight and thus might not be secure.

But I seen several photos online of wood blinds covering large windows and I don't understand how if they're so heavy, why folks still have them. I like the look of faux wood blinds a lot better than cellular but if weight is an issue maybe that's the way to go?

Your trim and windows are really nice, I would find a way to show them off without covering them up with blinds, curtains, etc. Good luck...

You do have enough room to mount but you will need returns on the headrail because they will protrude even if you remove the 1/4 round.

I suggest you do 2 or 3 blinds in a window that size. (Split where the windows split), because one big blind at 118x76 is far too big to warranty. It is 62 square feet, which many blind companies won’t even manufacture. you can request one continuous valance to cover the headrails, but I definitely would not recommend doing one giant blind in a faux wood. You’d be better with a Silhouette or a Duette (cellular shade) as they can be made for a window that size.