Jason,
Welcome to the forum. I'm sure you will find plenty of opinions to your design ideas. Everyone here is very supportive.
I noticed in your post that you want to fit a family of 6 into a teardrop trailer. I think you might find this to be impossible. Especially considering the fact that your children will grow at an alarming rate. Some here have rigged hanging cots to the inside of their trailers for children to use. This works for a while and then the kids outgrow them. The basic problem is that most teardrop trailers seem to max out at a width of 5'. This does not allow for sleeping parallel to the axle unless you are small. Some have gotten around this by building as wide as 6'. But at that point you start to get quite big for a teardrop.
If you have lurked on this site for any length of time you probably know by now how most people define a teardrop. It is a small trailer in which a person can NOT stand up. The classic "airfoil" shape is not a requirement of every trailer called a teardrop. Some are faceted and some are downright square. The greatest of the characteristics of a teardrop trailer is the ability to cook outside the trailer using a galley that swings open in some way. This cooking in the great outdoors is not only a lot of fun and very appealing to a lot of people, it keeps cooking odors out of the area in which you will be sleeping.
There are many people passing through this forum that decide to push the envelope when designing their ultimate trailer. People are experimenting with trolley top roofs and slide out sections. There are those that also build attached tents as a way of expanding the interior of their camping space.
When the building starts to get a little overscale or some of the signature elements of a teardrop start to disappear, we then refer to that as a "Tiny Travel Trailer". You will notice that is in the name of this forum. You haven't posted your ideas yet, so we don't know if it is really a teardrop you are designing or a tiny trailer. However you ultimately decide to label your creation, I have no doubt you will receive much satisfaction from the creative process involved.
Even though you have not yet shared all of your ideas, here is what I would do to give a teardrop experience to a family of 6.
Mom and Dad can sleep in the teardrop with a cot for the youngest children hanging above them. The median age children sleep in the tow vehicle. That is why a van is good. The older children sleep in a tent. One of the quick pop-up dome tents is perfect for this. It's not long before your children insist on bringing friends camping with them. That's why you need the pop-up tent. (don't put it too close to the trailer).
Everyone in the family gets to share the teardrop experience by taking part in the communal cooking that happens whenever people camp. If your galley is well thought out, you could provide food prep areas for people of various ages and sizes.
If children complain that they don't get to sleep in the trailer when you go camping, you can make it up to them by allowing them to have sleepovers in the driveway with their best friends. That way they get to "camp" also. Plan on using your trailer as a spare bedroom and you can get year round use.
I probably haven't told you anything new. I just felt like typing. . . But if there is anything of value in this post it is the idea that a teardrop trailer does not have to hold the entire family in order for the entire family to enjoy it. So much of the fun comes from the small size. If you make it too big, well then you have built something else entirely. Kids grow fast, so build a trailer that will please you and your wife. Then when they grow, help them build them their own trailers. Plan for the day when a family reunion is achieved by circling the teardrops.
Good luck
