1) Increasing the starting time from 16 minutes to 21 minutes increases the game time by 10 minutes;
2) Increasing the turn time from 8 to 8:30 increases the game time by approximately 15 minutes per player, calculated over a 1-month period (2-1-1), i.e., no more than 30 minutes for two players in total for the entire game;
3) Increasing the battle timer has the biggest impact on increasing the game time, as many "not-so-fast" players sometimes use up the maximum time, hence the long turns. For example, let's take an increase of 15 seconds per battle to the standard timer, with 4-5 battles per turn (and not all battles use these additional 15 seconds); calculated over 1 month, this is approximately 5 * 30 * 15 = 2250 seconds = 37.5 minutes.
So, where are your boasted 2+ hour delays?
The illusion of a long turn arises precisely during long battles, i.e., not battles that last 10-20 seconds, but those that last 40-60 seconds. This aspect has the greatest impact on the duration of turns/matches.