Elementary's aesthetics are in the right place, but Pantheon is probably too closely coupled with GNOME to allow the degree of freedom such a group would desire. Depending on GTK, which has become well known for pulling rugs from underneath devs using it, is also a liability.
Considering these things I believe such a group would be best served by starting their own DE project and likely writing their own UI framework with first-class C bindings, because while Qt doesn't break things as often as GTK does it's restrictive in the languages it can be used with.
Considering these things I believe such a group would be best served by starting their own DE project and likely writing their own UI framework with first-class C bindings, because while Qt doesn't break things as often as GTK does it's restrictive in the languages it can be used with.