Redesign Tasks as the place where you schedule, store, save, display and look up various interactions with prospects/customers. It can be the history log. It can be the input place to schedule future actions to be take. When completed, those actions remain as history. If their date is in the future, they can feed into calendars and Opportuntiy cards. See a small portion of Tasks new functionality.

This alone would give your CRM the fuel utility and power that it lacks.

In the center column of each Contact, combine all Tasks chronologically with emails, SMSs, etc.

Integrate Notes, and Appointments into Tasks. They are just "Types" of tasks.

But leave them as column headers to serve a quick views of key types of Tasks.