Choosing an apple tree
I'm new to the forum. Not sure what the level of interest is here for cider apples or heritage apple trees, but I thought I'd try my question here and see what info I can get.
I live in the city of pittsburgh, but with a nice-sized backyard. Along with the lot I inherited three very nice, mature apple trees. Two are red delicious, not my favorite apples, but mine are certainly better than the hard, tasteless, red delicious apples common at the grocery store. My pride and joy though is a tree that produces beautiful round, delicate but very crisp, golden fruit with a little bit of russeting. They vary from green in the shadier parts of the tree to yellow with a pink or red blush for the fruits that ripen in full sun. They are intensely sweet and tart and have a slight astringency in the skin. I don't know apple varieties well, but from what I've read I think it is most likely a "golden russet" tree. I understand that it is one of the better cider apples and I am interested in trying my hand at cider-making. I'm still in the process of acquiring the necessary equipment for pressing and brewing.
The reason for my inquiry is that my wife and I would like to plant a few more (not necessarily apple) trees to fill up the yard a bit. I figure if I'm planting trees I might as well put in another apple tree. I'm looking for input regarding an apple variety that would be a good compliment to my golden russet for cider. I'm thinking something on the bitter-sweet end of the spectrum would be good. It would also be nice if it was a good stand-alone cider apple as my golden russet tree is tending towards a pattern of biennial bearing and I don't a get a large crop every year. It'd also be nice if it was pleasant to eat as a dessert fruit, or useful for cooking or for some purpose other than cider.
My soil in western PA is heavy and a little acidic, and my lot is exposed at the top of a largish hill. Disease resistance is always a plus, but I have had very few problems with pests or fungus in my location. I've never had to spray for anything.
Can anyone recommend some good apple varieties to consider? Thanks for your input.