You could try to halve the trade export, but make the port income 200% (instead of normal 20%). That way, the AI earns more than you on your own networks.

Downside is that it will cripple the AI:s economy as soon as the networks breaks, due to the upkeep of his armies. The AI is poor on keeping a money reserve and cannot disband troops.

For 2. Haven't tried modding that part myself, but what does "office level" do? I was thinking if upping those might make a difference.