Creating groups with organic groups

Hi there,

I am working on my 1st Drupal project - an online community - and want to create groups with the following requirements:

- Groups are created by Drupal admin in the first place - perhaps later by registered users
- Groups are organized under "categories" e.g. Category A has Group A1 and Group A2, Cat B has Group B1, B2 and B3, etc
- Registered users can join groups
- Each group has its own specific Forums - users must join group to comment or post new topic
- Each group has a logo and a description
- Each group has 3 tabs: start page | forums | latest activity
- Start page contains blocks with events, resources, new members
- Forums page contains list of forums within that group
- Latest activity page contains feed of latest activity related to that group i.e. new members, new topics, etc.

I am thinking to user Organic Groups but I assume that I will need other related modules to achieve the above requirements.

I would appreciate if someone could suggest how to tackle this task. Which other modules would be required? Some specific questions:

- How do I create categories where I can then create groups?
- Do I to install OG Forum to create Forums within groups?
- How do I create a "a template" so that each group has the same structure i.e. logo, description, start page, forums page, latest activity
- Do I need OG Block Visibility to display content from other sections of the site?

Sorry for the broad question but any high-level suggestion to get started would be welcome :-)

Many thanks,

Greg