Simple UI but that takes a lot of time until we're accustomed. I want to customize more because "contact management" is my only problem.
Nice design, good classification for automatic retrieve information from your mail browser. Lack of a good agenda with the days and hours, where you can change everything.
All said I have tried some more expensive CRMs and none of them were great for personal management. I really use Cloze as more of a minder for my sales interactions than a CRM. I wish it integrated with trello or todoist so I could just have it run things while I use my preferred interface.