1) If you live in a colder climate, think about getting a heated floor for any full bathroom.
2) Dishwasher should be right next to the sink and the cabinets that will store dishes and silverware should be right next to the dishwasher. Much easier when loading the dishwasher with dirty dishes and then unloading the dishwasher of clean dishes into cabinets this way.
3) Smooth countertops. I've lived in places with either tiled countertops or textured countertops and I absolutely hated them because they never felt clean.
4) Undermount sink is a must. Easier to clean.
5) Really, really think hard about workflow in your kitchen. Will you have only 1 person at a time cooking or will you have 2 people cooking together a lot? Will your workspace be set up so that you can work independently or will you be tripping over each other? Also, will your fridge be next to the area where you do most of your food prep? Will your canned and box goods be right above that as well? What about spoons, spatulas, measuring cups, knives, etc?
6) I've lived in a few places with a kitchen island I'm very 'meh' on them unless the workflow of the kitchen is laid out nicely.
7) Kitchens tend to be a focal point of the house if you have a nice one. Think about putting in a bar type area with a few stools on the other side to fit 2-4 people.
8) Have a tall shower head. Shower heads that are 5 feet 2 inches from the bottom of the tub are horrendous. Get one that at least 6' high or if you can afford it, get a rainfall shower head.
9) Get a deep tub if you are replacing it. With most tubs in modern houses, either your knees or boobs (for a girl) are out of the water. If you like relaxing in the tub, get a deep one so that the only thing that is out of the water is your head. Better yet, get one that fits 2 people like this.
10) When I was searching for ovens, I found that only 3 features mattered to me: self cleaning, window & light, auto off
11) Storing of spices seems to be a pain in the ass. Think about how to use some small spaces to have built in spice jar storage.
12) You may also think about having hidden garbage and recycling containers as well.
13) Glass front cabinets are horrible. My OCD is bad enough that I don't need to be concerned with organizing my kitchen cupboards as well.
14) Under cabinet lighting is a must. If you are working in the kitchen, there is likely to be a light in the center so your body will be blocking the light getting to your workspace. Under cabinet lighting fixes this.
15) Think about how you want to store your pots, pans, and knives. Many people like to hang them up so that they are easy to see or find. I personally like them hidden. But in my current house, I put them in a place that is kind of a pain to get them out because it was the only cabinet that was big enough to fit all of them.
16) You have these awkwardly big small appliances such as a pressure cooker, stand mixer, blender, etc. Where are these going to go and how to get to them easily.
17) Everyone has a junk drawer. Where will yours go?
18) Watch out for appliances blocking drawers. In my current house, my cooking utensil drawer is blocked by the fridge so that I can't open it the last 2 inches.
19) Hood vent over the stove should vent outside. Venting it back into the kitchen is worthless.
20) Get furniture grade plywood instead of particle board/MDF if you can afford it. It will last longer and be more resistant to any kind of moisture damage.
21) The area under the sink gets nasty because that is where a lot of cleaning supplies go. Try to either get a custom fit tray that goes there or get some kind of finish on it and about 1" up the sides that makes it easy to clean and last for years and years.
22) Lighting is key in both the bathroom and kitchen. My master bath has horrible lighting and it sucks.
23) Bathroom vents that are on timers are good to have. Quiet is good, but focus on ones that move the most CFM to properly vent a bathroom.
24) Towel holders for the bathtub and for the sink should go into studs and not be anchored into the drywall alone. I've seen many ripped out accidentally.
Is that enough for you?
EDIT: Added stuff for 10)
