I have a similar problem - everyone else (who has never bothered to take out a tape measure or even understands the concept of "standard" sizes) thinks I can magically fit the entire world, along with the kitchen sink, into the kitchen! And, for some bloody reason they are OBSESSED with windows - exactly where they do not fit! For example, everyone thinks we "must" have a window looking into the back yard (on the shorter wall), but they do not realize that you cannot put a window behind the fridge and freezer! So I managed to put a cooktop between the fridge and freezer, so I could squeeze (literally) a window in there. It's so DUMB! They all seem to think that the window can be used as a pass-thru to the deck outside. Honestly, I think that is highly impractical, considering it would have to be a casement window that would interfere with what goes on the deck, and you could not have a screen, so bugs would come into the house, so it would never be used as a pass-thru! It's really hard to tell the layout of your kitchen - the only measurement you give is that the sink wall is 12 ft. Well, that is about the same size I am working with, and my sliding glass doors also limit the length of my L-shaped kitchen (interestingly, everyone's "dream window" would be about where yours is). Do realize that you will need a corner cabinet if you extend onto the door wall - I advise a blind with a really good pull-out over a lazy susan because they only take up excess space along one wall (instead of 36" along BOTH walls), plus they are more efficient). That being said, I HATE corner cabinets - that is currently the bane of my existence! It's hard to tell from your pics, but I assume that the entire wall behind your range was knocked down and a header goes all the way to the window wall, correct? And you want to eventually arch the entire opening (long shallow arch)? How long is the peninsula wall? Is it 8 ft (30" cab, 30" stove, 36" corner cab) or does it also include where the fridge currently is approx. 36" = 11 ft? I am assuming the whole thing was headered out, but there will be a doorway where the fridge currently is. You call it a "peninsula" as opposed to "half-wall" therefore I assume that you can enter the kitchen from the dining room where the fridge is now. Or will the doorway remain (I assume) across from the front door and the peninsula extend to where the fridge is now? Either way, if you are going to arch out over the peninsula, I'd also arch (curve the corners) of the doorway, otherwise it will look really odd (square next to arched). I'm assuming there are studs between the doorway and peninsula (because a header longer than 12 ft would be really expensive), so I would build it out to at least 12"-16" (the vertical part - the base "holding up" the arches) both between the doorway and peninsula and also at the other end where your corner cabinets are. This way you will not see the sides of those corner cabinets from the dining room (a MAJOR pet peeve of mine), and it will actually look like a well thought-out deliberate design. Nothing looks worse than an archway sitting on "sticks" (just wrapping 6" of studs with drywall). You can also use this vertical space to hang wine racks. As for your range, NO! Do not install an island hood floating in the middle of your archway! You say there is 58" between the wall and window; I assume that means you are including the 24" depth of cabinets currently there. If that last cabinet is 36", then you can replace it with a normal 36" lazy susan cabinet. Even if you get new cabinets that will save a lot of money because you will not have to move the plumbing for the sink and d/w. That would take up 36" on the door wall, and if you put the stove immediately after the corner cab it would land half way under the window; if you put a 21 inch cab and then the range it will land directly under the window. At best you would need a new window because the high back of the range will be above the bottom of the window. Then you still have the dilemma of the range hood. CAN you put it over a window? I suppose, unfortunately it is very difficult to make look right, and I did fit that into my plan for that stupid "dream window" everyone wants, but it sure is a pain in the butt to design around! Personally, if I was getting new cabinets I'd do a 12" drawer bank next to the d/w and a 42" blind cab along the door wall. Then the range, another drawer bank, the fridge, and end with a base cab - do not end with the fridge right next to the door - you ideally want a counter on each side. Plus, it feels claustrophobic to walk in next to a fridge or tall cab, and you want to be able to set groceries there. I don't know how long your wall is to the door though!

We can't see your style from the pic posted. If you want to emphasize the height of the wall, go with tall, vertical art like the insp pic below. I'm not sure if the tapestry works with your style or not because we can't see the rest of the room in that pic.

Napoleon makes OK fireplaces, but their efficiencies are terrible. The P4 Energuide efficiencies of their Luxuria Series of linears range from a low of 38.8% to 52.5% Which means that in the case of the LV38N 61% of the gas you pay for is wasted and the best LV74N almost half is wasted. The Valor Linears range from 66 to 70% P4 Energuide efficiencies. The Heat Shift allows TVs and other heat sensitive items above the fireplace as well as combustible wall materials up to the fireplace opening. Here is the Heat Shift Video.

I'm not a contractor, but I don't think you can put anything on top of blacktop like decorative stone or tiles. When patios are built they are put on top of several inches of stone of various sizes to create a bed for the stone that will prevent heaving during freeze/thaw cycles. It would probably be a better idea to put decking over it. However, as soon as you permanently cut off your garage from your driveway you may be impairing the value of your property. Is this the only side of your house that has access to a flat piece of ground suitable for a patio or deck? I don't think a fence is a problem. There are plenty of people who fence their backyards and that includes having a fence (that opens) across the driveway. So would just dressing up the area with some planters and patio furniture work for you? An umbrella for the table or a pergola would look nice too.