Groups and subgroups - Missing something

Hello Gliders!
We’re trying to make and App where people can customize they’re own architecture plans. On this prototype we simply want people to:

1 - Choose the architectural model (6 options)
2 - Choose the interior design option (3 options)
3 - Choose the color palette (3 options)

With that the user would get the “customized” plans from the 54 variations possible (6x3x3=54). I’m definitely missing something on the “Groups and Subgroups” feature. Tried several different ways, but I still couldn’t get a “clean” sequence of clicks for the user interface. Hope you guys can help me out!

Here’s the link for the app:

I would break your data into 3 sheets. The first sheet would contain Models. The second sheet would contain Interior Design Options. The third sheet would contain all Plans grouped by Color. Your main tab would first show a list of Models. You would select the model to view it’s details. To link the model to the Interior options, you would set up a relation from the model sheet to the Interior Design sheet. The Interior Design sheet would contain each interior design option for each model. The relation would be between models on the Models sheet and models on the Interior sheet. A similar thing would be done between Interiors and Color/Plans. With that relation you would then add an inline list to take you to the details of the next sheet that is the next level down.

Another alternative would be to have a sheet with a record for each user. When the user is viewing the details for their own record, you could have 3 choice components where a user can select the three options needed for a plan. Using a template column you could build a value that is a combination of the 3 columns and would be used for a relation to link to another sheet with the 54 plans. You then add a list that uses the relation and that will get you the plan you want.