I’m just gonna start with the sink: Maybe there’s a good reason to use a bar sink in a tinyhouse, but personally, I think you’ve got to watch out for the same sort of thinking that leads people to put extra small handles on the smaller kitchen knives. I mean, smaller knife, smaller handle, right? But you hand stays the same size…. granted you need less leverage for a small knife, but a lot of expensive knife brands have realized the error of this way and use more or less the same size handle on the different knives.
The next thing I think is kind of funny about small kitchens is their lack – yes, lack – of appliances. I stumbled across the Samson Ultrasonic vegetable cleaner recently. Good idea, a machine that washes vegetables. I’m not entirely sure ultrasound is the best way to do it, but whatever. It can also be used for cleaning dishes and all kinds of other stuff too, without so much as the need for detergent. If I had a tiny kitchen, I think I would want to have an assortment of machines that makes sure I only spend the minimum amount of time in said kitchen (while still eating really healthy). It might not be the usual sort of thing that people think of as a kitchen appliance, but any task that can be automated should be, I say.
Storing food is another potential problem in a tinyhouse. Obviously this sort of thing is compounded if there is more than one person living in the house. One thing I’ve found handy personally, is vertical space storage. If you think about it, storing stuff in a cupboard tends to leave a lot of unused volume. If, for example, the kitchen counter were designed to flip up, revealing a storage compartment, gravity makes sure stuff gets packed together a bit better in this situation. I’ve been doing this with relatively tall cardboard boxes to extend the amount of storage space I have, and it works pretty good for large stuff and infrequently used stuff – so bulk foods, then, and some kitchen equipment. For more frequently required stuff finding stuff is a bit harder. You want more than one container, because the finding process sort of necessitates taking stuff out of the box and putting it somewhere else (e.g. another container or onto a nearby counter), while you dig deeper into the box to get at stuff below.
I also like the idea of trap door cupboards in the counter top to store appliances. To use the appliance, instead of taking it out of the cupboard you can just open the trapdoor. There would be an electrical outlet inside the compartment, with a way to keep the electrical cord away from the (hot) appliance. You might want to put a safety switch on the door so the outlet is turned off when the door is closed, too, keeping the appliance off.
Glass cooktops are pretty cheap now, and they can be used as counter space when they are not turned on, so having a full sized cooktop is no stretch. An oven, though…. Well, it’s just that if you could use the internal space of an oven, e.g. store stuff in the oven, it would take a lot less space when you weren’t using it. Only how do you prevent the oven from being turned on while the stuff is inside it? Maybe you could require that the oven door be opened fully for a few seconds every time, before the oven can be turned on. That would make people look into the oven before turning it on. You could have a sensor that verifies the oven is empty before it can be turned on (but you can put stuff in after it is on). The other thing, I figure, is the baked on food in the oven. An insert box that went into the oven cavity might be a good idea, you take it out and put it on the kitchen counter or nearby before starting the oven. Have the oven racks fold up against the back of the oven or something so they don’t need to be removed each time.
Another idea might be a foot controlled faucet, maybe not for everyone, but I like the idea of being able to hold onto stuff while I’m controlling the faucet. It cold reduce water usage, too. There are devices available to do this, but I would want something that’s a bit different than what they are offering, I think having separate temp and volume controls that could be set and then did not need to be held in position would be better.
Heated appliances should all be insulated and use heat exchangers where appropriate, of course, I’ve noticed that a lot of heated appliances like rice cookers seem to be entirely uninsulated.
Oh, and about the fridge and freezer, a deep freeze can be used a fridge, and a small deep freeze would be much more energy efficient and for a lot of models, quieter, than a bar fridge. Bar fridges are actually terrible for both those things, because they are very poorly insulated, and powerful compressors make a lot of noise, too. It might make more sense to put an upper level that was fridge, and have the lower level freezer (with insulation in between.) or actually, what I was thinking for my own purposes, was a freezer with an external cooler, with a convection powered coolant loop so the compressor in the freezer cools the fridge, too. Basically just take some food grade pvc tubing from the brew your own, put 2 holes in the freezer, probably in the seal for the door, then run the tubing in, around in a coil, then out, and then run it into the cooler, through a coil inside of a plastic bottle filled with water, then out, and close the tubing loop. Then you need some sort of insulation around the tubing where it runs between the fridge and freezer, to reduce the entry of heat. The fluid in the tubing would be something that would not freeze to soon, like an alcohol and water mix. Then, to regulate the temperature inside the cooler, that is what the plastic bottle filled with water is for. The coolant loop runs through around the inside of the bottle, so when the temp. of the water in the bottle gets to around 0 deg c, it starts to freeze to the coolant tubing. That impedes the flow of heat, reducing the amount of cooling provided, helping to keep everything at around 0 deg c., just right for a fridge. The flow of the coolant is entirely convection powered, so the heights of the fridge and freezer have to be appropriate. The size of the water bottle etc. would have to be sorted out, of course.
edit: There is a company at yesweecabins.com, and the builder explains why he uses full size sinks in one of the videos.