Need to use it for a selected group of people

[SuheylZ]

I'm currently using an email client, provided by the email service provider for a selected group of people. that email client is very basic, hosted on their domain and offers very little customization. I'm looking for the following

1. DEFAULT DOMAIN NAME: User should only enter email before @Domain because all users are on same domain.
2. DEFAULT EMAIL SERVER: Email client should talk to this particular domain by default. i.e it needs to append @Domain when connecting with server
3. ORGANIZATION THEME : I should be able to apply custom theme (colors and logo) which is the default for users.
4. DIFFERENT TIMEZONES: users can have different time zones and their time zone should be used.
5. HOSTING ON SUB DOMAIN : If I host it on a subdomain like email.domain.com the login page should be visible with the customized theme and after login it uses the user's time zone (also available from the email server)

Can anyone help me tell which of these features are present in Kan-email already?