I rewrote my code a bit less lazily to take reinforcements into account. So these are purely the player's incomes. My database has about 150k games, so, by no means, this is a complete list.
Turn 5: 22 income max (57 examples): (Combination of bonus and the number of examples of this combination of bonuses_
- SEA + West China + East China + Indo: 48
- Greenland + Scan + West Russia + Cauc: 4
- East US + West US + Central America + South America: 3
- Scan + West Russia + East China + West China: 1
- Central America + South America + West China + East China: 1
One combination is much more common than every other combination. I would attribute this that many of these games feature an East China FTB as start (though a SEA FTB works as well), giving much more armies, and there are even a few armies left to spare during turn 4 (which is not the case for the other variations). In all games I checked manually (~20), there was an FTB taken.
Tacky posted a Ant + Aus + West Russia + Cauc variation, which is very rare and not in my 1v1 ladder database.
Turn 5: 29 income max (2 examples):
https://www.warzone.com/MultiPlayer?GameID=12865252 and
https://www.warzone.com/MultiPlayer?GameID=13715763- West Russia + Central Russia + East Russia + Cauc + West China: 2
Turn 6: 35 income max (1 example):
https://www.warzone.com/MultiPlayer?GameID=11836160- Scan + West Russia + Cauc + West China + East China + SEA + East Russia
Turn 7: 42 income max (1 example):
https://www.warzone.com/MultiPlayer?GameID=11376266- Greenland + Scan + Europe + West Russia + Central Russia + Cauc + East Russia + West China
Turn 8: 48 income max (1 example):
https://www.warzone.com/MultiPlayer?GameID=15580457- A lot
Turn 9: 53 income max (1 example):
https://www.warzone.com/MultiPlayer?GameID=13131161- A lot
Turn 10: 58 income max (1 example):
https://www.warzone.com/MultiPlayer?GameID=17743423- A lot
