Ok, so as a working theory, I've picked 4 varieties, but I may only go with 2-3 depending on if I need to plant any pollinators (I still have to look that up).
Any thoughts?
Bittersweet: Tremlett's Bitter
Tremlett's Bitter fruit are medium sized and have a hard, bittersweet flavor, high in tannin. When blended with a sweet and a sharp cider apple, they help create a rich, refreshing overall flavor. Tremlett's Bitter is considered a bittersweet hard cider apple. Firm, medium size, apple. Good for blending, not much needed to spice up the cider.
Harvests September – October. One of my personal favourites and definitely one to get hold of if you have a high level of ‘roadside’ apples. Stephen Hayes describes Tremletts as a cider condiment, and I would agree, as it is so bitter it is almost inedible. Will give body to a weak cider, although does not have a great character of its own. No experience of growing, although does tend towards biennialism.
Bittersweet: Harrison
Originated in Essex County New Jersey before the American revolution and highly prized. The apple is yellow and elongated with rich yellow flesh. It produces a superior sweet cider. They are often picked when they fall in November. Trees are strong and vigorous.
The Harrison apple enjoyed the highest reputation as cider apple over a century ago. Originated in Essex County, New Jersey which at the time, early 19th century, was the most celebrated cider making district in America. It was grown extensively throughout Eastern United States until 1900. The flesh is rich, yellow, firm; pleasant and sprightly, but dry. Harrison apple juice makes an extremely dark, rich cider. The apple is scab resistant, and stores well. It remains one of the very finest apples for cider-making, either fresh or fermented. Historically planted for cider with the Campfields.
Bittersharp: Kingston Black
Perhaps the epitome of all cider apples, Kingston Black is the most sought-after bittersharp variety in the States. This West Country English apple provides an ideal balance of sugar, tannin, and tartness without blending, and is considered to be the finest choice for making a single varietal cider.
Sharp: Redfield
Redfield is an unusual apple / crab-apple cross. It's key feature is its distinctive deep red flesh. The red pigmentation of the flesh also extends to the younger leaves and the wood of younger shoots.
The flavor for eating fresh is not great, but Redfield produces a particularly attractive red cider. Like Wolf River (its apple parent) it is also an excellent baking apple.
Redfield is cold-hardy, and easier and more reliable to grow than many red-fleshed apples.
Like many red-fleshed apple varieties, Redfield is related to Malus niedzwetzkyana, a species of crab-apple originating in central Asia and characterised by purple-red flowers, purple leaves, and red or pink fleshed fruits. Redfield was developed in the 1930s at the New York State Agricultural Experiment Station, and is a cross between Wolf River and Malus niedzwetzkyana. The fruit size is larger than most crab-apple / apple crosses, as might be expected given the very large size of Wolf River apples.
Edit: I figured out that Harrison is a bittersweet.