I would like to suggest the inclusion of a new tab in Google Trips app, named My Places, which would be an inventory on Google Maps lists the traveler had chosen as relevant for that trip. Those lists (Your Places in Maps) could be create by the traveler (private or public) or by others (shared or public). Thus Google Trips and Google Maps -which is a key tool for travelers- will be even more tied. So, when you find out -or create- a list in Google Maps, you should have the choice to vinculate it with an existing trip in Google Trips and consequently create a direct access from it. Logically, as every trip in Google Trips is related to a location, the Lists could be proposed to the user based on that location and other relevant data of his/her profile. From my humble opinion this will improve the traveler experience, specially when at destination. Eager to know your opinions, best regards,
JAVIER GONZALEZ-SORIA