"give_trait <character> <trait> <trait level (single number)>"
Like:
give_trait "Avlvsaccivs Cotta" GoodTactician 5
If you want to cheat to give some general command skill. Or give some enemy some traits that make them easy to assassinate.

"create_unit <character/city> <unit> <amount (1-5)> <experience> <armour> <weapon>"
Like:
create_unit "Roma" "roman infantry polybian triarii" 5 9 3 3
To create some super armys out of nowhere.

I also use (rarely) the before mentioned:
toggle_fow
process_cq <city>
add_population <city> <amount (1-4000)>
auto_win attacker
auto_win defender (ambushing the enemy on their turn counts as an attack)
add_money <amount (1-40000)>
show_cursorstat (for location of the arrow compared to coordinates of the map)
add_money <faction>, <amount (1-40000)>