My sympathies. Boots are one of my favorite items to wear but one of the hardest things to shop for. We have such an abundance of great boots this season, and the only pairs I've seen that really "lit my fire" are not viable options due to my calf circumference.
Rangers: They are kind of a dark brown - not really chestnut and not quite chocolate, but a medium brown. They barely have a heel - very chunky, and in the picture it almost looks lower than 1". There is a strap with buckles that runs vertically from the top of the boot all the way to the ankle - I think the strap is around 1" wide, and the entire strap is surrounded by an elastic gore panel, which means that the boots should be stretchy and form-fitting. The toe shape is pretty round.
I think they look like a very sleek pair of riding boots, and I'd go for them myself in black!
Faith - a bit sleeker & less "equestrian" than the Rangers. I could see you wearing this with some of your dresses, such as the beloved cobalt blue dress, with black patterned hose. The heel looks slightly higher, and there is a 1" strap running horizonally across the front of the ankle with a buckle at the side. The elastic gore is on the inside of the boot and is only about 3" long, so the stretch will probably be less forgiving in the rest of the boot. These also have a round toe.
Carly - The heel is quite a bit higher & thinner than the Faiths, which you probably already know from reading the product description. (It might be less stable to walk in.) There is a long seam on the outside of the boot - maybe 1 cm wide - running all vertically the way down, and a built-in seam or strap placed horizontally around the boot above the ankle. The buckle is in the back. They are pretty and sleek, but personally I prefer the Faiths over the Carly pair. The toe is somewhat round but looks narrower than the previous two.
Valentine - A bit dressier IMO than the previous pairs. The heel looks lower to me than the Carly pair, but is still not very chunky/substantial. There isn't a lot of detail on the front other than a thin vertical seam down the front of the boot, but on the back there is a very pretty laced seam running vertically down the boot almost to the ankle. It looks like the back seam would allow for a very close fit. The toe shape is somewhat square.
Ella - these have quite a pointy, elongated toe. The heel is VERY narrow. There is a thick elastic panel in the inside of the boot - about 1.5" wide and 3.5" long, I think. (They don't look like they would be the best boots for running around the city with Reta - I would scuff the toe all the time in them!)
Simon: These actually remind me of the Faith boots, minus the ankle strap. There is a stretchy, V-shaped panel down the back of the boots and a zipper running from the ankle to about 2" from the top, so I think that these would be easier to get on than the average OTK boot. Looks great and not "pirate-like" when folded over. I vote to try them!
Overall, my favorites are the Ranger, Faith, and Simon pairs of boots. Good luck in your search!