I agree. It would really great if CA could have some scale of relationship in diplomacy built into RTW. Developed along the lines in other games such as EUII.

For Eg.

Each faction has a 0-100% friendship rating to every other faction. This rating would be affected by similarity of culture, marital alliances, history as reliable allies, treacherous breaking of treaties / alliance, long years or warfare, sacking cities, pillaging crops, armed assistance, gifts etc etc etc.