Just take a look at what height your taps are in your current finished bathrooms. The height is not something that has to be standard, as long as it is comfortable for you.

My post from another thread: "I'm not sure of their retail prices, but try Bermex. I have a pedestal, non-extending, 36" (I think) table from them in my kitchen. That and four chairs cost me about $1600. You can customize just about anything." I don't know if they will have the style you like, but they do have counter height tables (like my kitchen table). Here is a link that might be useful: Bermex

What makes a chair comfortable isn't the padding or lack thereof. It's all about the shape of the seat and the shape of the back and the angle where the back of the chair meets the seat. I have a wood desk chair with a shaped seat that is far more comfortable than many padded chairs I've sat in. And for dining chairs, another big factor is the height of the seat in combination with the height of the table. If you want comfortable seating in your dining room, that will encourage people to linger after a meal, you really need to test the table and chairs together. I suspect that when people say a dining chair is comfortable, it isn't just the chair; it's also the way the chair and the table work together that makes the seat so comfortable. I'm sure it's possible to get a very comfortable counter height dining set, just as I know it is possible to get an uncomfortable regular table height dining set. So whatever you get, I hope you can test sit it first.

I don't know what you intend to do regarding backsplash height (that's the distance b/w the finished counter and the bottom of the upper cabinet and light rail), but here's what I usually tell people when they're considering the height for their backsplash. The standard is 18"...regardless of the reasons why, it's still the standard.. How this affects your kitchen.... Refrigerator and other tall cabinet heights...Because wall cabinets are meant to be mounted at a standard height, cabinet manufacturers take this into account when designing tall cabinets. Tall cabinets are designed to be the same height as the installed wall cabinets so the tops all line up. When you change the height a wall cabinet is installed at, it affects cabinet top alignments. With the refrigerator you can usually mount the upper cabinet a little lower OR order a shorter upper cabinet, but be sure you don't make the alcove any shorter than 72" tall b/c newer refrigerators are 70" to 72" tall (and seem to get taller each year!) With other tall cabinets like oven cabinets and pantry cabinets, they're a standard height and designed so they're the same height as the wall cabinets when those wall cabinets are installed 18" above a 36" high counter. If you have custom cabinets, this may not be an issue b/c your cabinetmaker can adjust the cabinet heights. But, if you are using stock or even some semi-custom cabinets, you cannot change the height. You can often get taller cabinets for use w/36" or 42" tall wall cabinets, but not shorter for 30" mounted lower. But, even those that are taller are also adjusted based on standard wall cabinet heights + an 18" backsplash height. Small appliance height...Small appliance manufacturers often design their products to meet this 18" standard...for example, my KA stand mixer (bowl lift) is around 17" and many coffeemakers and blenders are just short of 18". So, you need to be sure you have room under the cabinets + light rail to fit those appliances. Small appliances... Keep in mind that if you're using an appliance on your counter, you must be sure you have room under the base cabinets to move that appliance around easily. Don't, for example, tell yourself you're only going to use it in front of your upper cabinets so you don't need to worry about its fit. In reality, you will be moving things around on your counter while you work and most likely your appliance will be moved under the cabinets at some point. You don't want to tear your light rail off or damage it (or the cabinets). Also remember that "standard" upper cabinets are 12" deep + 1" for the door...so they stick out 13" over your counter...leaving you only 12" or so of workspace in front of the upper cabinets...not much room to work in by itself! (If you have deeper upper cabinets...say 15", there's even less counter frontage in front of your upper cabinets...3" less, so 9".) Vertical workspace... Another consideration is vertical work...