Said it before. If you cannot implement some simple task without deep changes in the engine, it’s not really “lightweight”, it’s “missing features”. Or outright missing features, e.g. no networking in Web builds. I don’t mean Urho cannot be used. It totally can and Urho community prove it. But it would be lie to say that Urho don’t miss anything.
Also, only a person who never looked at Urho renderer code can call it “lightweight”. It’s complicated as hell. Ever looked at View.cpp/Batch.cpp?