Show only rows with highest values
In Drupal 7 there was the Views Reference Filter. 

Basically, what you're after is filtering one view with another (if you have to go through the interface and not code a custom solution). Those database queries can be quite slow so you're advised to use caching. 

Views Field View has the D8 version. The strategy is to create two Views displays, one listing Users, the other Views listing only one node sorted by Value descending and with a contextual filter for UID. Then you insert the second view into the first one (as an additional field). 

This way you get the one node that has the highest value for the particular user.