EVen using an app or mobile device the collection of map coins is a time investment
visiting 50 players at one time gave you significant extra coins but lately one has to do 100 player helps to recover coin losses at least
I worked out an actual example for the same province/level and the lower level player would have had to do 67 visits to make up the coin from NH and the higher level player 156 visits from NH. The difference in the two examples was for the same province, same level, one player needed 12.96% of their main hall coin capacity, and the other needed 25.92% of the main hall capacity.
Here's my analysis of coin from NH.
Looking at the coin again, until level 17 the main all gave a constant 0.3% of its capacity for NH. Level 19 give 0.27%, level 21 gives 0.25%, level 23 gives 0.23%, level 25 gives 0.21%, level 27 gives 0.2%, level 29 gives 0.19%, level 31 gives 0.176%, level 33 gives 0.168%, level 35 gives 0.1674%, level 37 gives 0.1667% and doing chapter 17 for level 39 gives 0.15%, so since Dwarves the value of NH relative to the main hall has been cut in half.