I'm not entirely sure which direction you're going in for the "new 'kind' of LEGO - but as you point out, unless this is based around existing LEGO elements Ideas is probably not for you:
Your models may only use existing LEGO parts. We do not allow suggestions for new LEGO parts.
So unless it's based on System (and by extension Friends and Elves) or DUPLO you're probably out of luck there - from an older Cusoo FAQ:
Models should not depend on new LEGO element molds. While we love considering new elements, if a model depends on a new element, there are more potential factors on which it can fail review. [...] An existing element in a new color is OK, but a new element in one set isn’t likely.
You might get some traction through the Marketing teams, as product development comes under the "Marketing and Products" division under the CMO - for example the 2011 edition of "The LEGO Group - a short presentation" talks about there being a number of "product development deparments", while the 2014 edition shows "product group 1" and "product group 2" and both state that:
Concept and product development takes place primarily at our Billund headquarters in Denmark. The LEGO Group also has a listening post in Los Angeles to help monitor the