I started using Odoo for CRM trying to move from Capsule CRM, unfortunately I feel the Odoo's design quite poor compared to Capsule or AgileCRM that is another CRM application I was testing.

So my question is direct: Is there any contributed CRM that you could recommend for improving the CRM experience?
or in the worst case how difficult could it be to modify the native CRM application to make it more like my tastes?