Started new game and found myself blocked by Ragnar from east and zara from north
moreover, zara settled city near me on 10 river tiles. BW not revealed bronze near me, and approx ~1000BC ragnar who had "enough on hands" showed stack axes near my city. it was crappy spot in tundra with fish.
I simply gifted this city to ragnar. He jumped on pleased (+4 trade relations) , moved out his forces from my border and 2-3 turns later wardecced on zara
at this time I teached IW, connected iron and whipped some axes/swords. Declared war on zara, took almost without resistance 2 of his cities when he was busy with ragnar.
So I think I found pretty exploitive thing. You can trade 5-6 turns in your capital for +4 relation. This is huge bonus on early stage when no other diplo modifiers like trade/religion/etc
moreover, zara settled city near me on 10 river tiles. BW not revealed bronze near me, and approx ~1000BC ragnar who had "enough on hands" showed stack axes near my city. it was crappy spot in tundra with fish.
I simply gifted this city to ragnar. He jumped on pleased (+4 trade relations) , moved out his forces from my border and 2-3 turns later wardecced on zara

at this time I teached IW, connected iron and whipped some axes/swords. Declared war on zara, took almost without resistance 2 of his cities when he was busy with ragnar.

So I think I found pretty exploitive thing. You can trade 5-6 turns in your capital for +4 relation. This is huge bonus on early stage when no other diplo modifiers like trade/religion/etc