I'm happy to help you. I know PA is a really tough market to build a great steakhouse list. I'm the wine director at Del Frisco's in Philly. Feel free to reach out to me.
Looks like I'm a few days late on this one but I would echo what Christopher says on the more esoteric varietals. Make those 10% of your list to start and then assess the market. You'll upset investors if they're sitting on stagnant inventory out of the gate.
As for the obvious Cali Chard, Pinot and Napa Cab, don't forget that in this category, people become brand shoppers. They don't want just a $150 Napa Cab, they want THEIR $150 Napa Cab. You need to have at least a half dozen labels of each of these categories. Try to find your diversity in style, AVA, and price point. Someone looking for Rombauer Chard isn't going to be happy with settling for Cakebread. Faust and Silver Oak are nothing alike.
Don't forget that steakhouses are one of the few environments where people spend money like water and where you don't need to overthink your list. Most of the list will sell itself so your servers don't need to know the wines per se, but they need to be familiar with knowing how to identify them on the list, and be proficient in the service of them. You're going to go through more Nickel and NIckel than you will your Douro red BTG. Take advantage of this. Make sure your BTG program helps you to hit your margin and then get those top line sales form your blue chip wines by the bottle.
You also need to build some relationships which is difficult in PA but you're not necessarily going to be able to just buy some Hillside Select out of the gate. Your state supply store may not carry things that you planned to have on your list so you'll need to build a relationship with the store manager and distributor to make some things happen. If you have a mentor you currently work with or have in the past, have them make introductions for you. SO much of this business is relationships.
Some gaps that I see on your theoretical list besides having a greater selection of the big three (Chard, Pinot and Cab)
Chablis - I don't know a steakhouse that doesn't offer raw barSancerre - see above and its also just so well known to people nowRose - so hot right nowMore Bordeaux - but sadly the suits to buy it as much these daysSuper Tuscan - Everyone here would probably rather drink Brunello but you'll sell the hell out of Super Tuscans 10-1 vs BrunelloMore Barolo than Barbaresco - the spenders know it better. Italy will likely be your dog between US, France and Italy but Barolo will always sell in steakhouses and you can have the range of 100-500 and usually find some aged wines. Burgundy - I wish it was a bigger seller at steak houses but you need some for window dressing at leastPetit Sirah - a varietal I always overlook and when I put it on, it inexplicably sells like crazy in that setting. Turley or Stags' Leap are good options for thatDon't be afraid of MerlotFor something a little more esoteric, sagrantino is a good steak wine. When I actually would get a drinker who wanted me to find something for them, I always pushed northern rhone for france, and sagrantino for Italy and people were always happy. Arnoldo Caprai's is what I've been working with.