There is a plugin that gives a Group Hierarchy which will probably be useful for you.If you can be more specific about what you want then there will be other plugins to recommend for your specific needs.
It looks like it is in active development so you might want to suggest the features you are looking for to the plugin author if it doesn’t already cover your needs.
This sounds like something that can be achieved without multisite.You can use Buddypress Groups and bbPress running as a forum for each group to achieve the discussion / chat.
Each project could become a BuddyPress Private Group with its own forum / docs.
If you want a seperate blog for each project then that would require multisite,but one blog categorised by project could achieve the same thing without the additional comlexity.
It sounds to me like this is a two site WordPress Multisite setup.Your best starting point is set up one site then read the WordPress Codex on setting up multisite and add the project management site as a subdirectory or sub domain.
Adding a forum to a group when BuddyPress and bbPress are installed is part of the group creation process,so you – or anyone with Admin level capabilities – would make the choice either when the group is set up or later as part of a review process.
bbPress works without buddypress so it is possible to add forums without installing BuddyPress.You would have to evaluate the features of each plugin that are essential or optional and then make a judgement about the combination.
The easiest way to evaluate the features is to set up a test site and play with different combinations.
There is a WordPress plugin called Job Mamager written by scribu that can handle what you are looking for, or you could set up a group for each vacancy and let people join the group to express their interest and use extended profiles as a CV.
i’m not a developer but am planning a site which matches people to jobs in a similar way using this plugin.
simple-man,
I prefer to run the bbPress forum plugin as it integrates well with Buddypress.Using a forum plugin is a way to get your site members and visitors to engage in the discussion and encourage them to return to the site regularly.
It really depends on the specific community,some prefer to comment on a blog or podcast,others prefer forums.All you can do is set up one forum and invite people to take part and then make a judgement about whether the level of interaction justifies a forum per group or just a forum for certain groups.
The difference is in the scale and the level of complexity.
buddypress + WordPress on a single site is relatively simple to setup
wheras Buddypress+ WordPress Multisite is more complex and requires additional hosting resources
The functionality difference is on a single site install your users will be posting to a single blog whereas on a multisite instaall each user would have their own blog to post to.
If you are just seting up the site then my advice would be keep it simple and go for a single site WordPress+Buddypress setup
I’m a great believer in keeping things simple,and WordPress Multisite creates an additional layer of complexity which you probably do not require in initially.
