The dev. team are currently looking into allowing you to stay on the menu that you purchased an item from so that you don't have to start all over again.
This is also in the works! Hooray!
In regards to higher priced HQ items being filtered due to multiple NQ items being listed, while we can't make specific promises, the dev. team is looking into ways of preventing this (whether it be separate categories for HQ and NQ or something else).