Why use Confluence?
- Excellent Rich Text Editor - One of the strongest features at all, it for sure beats all other CMS Editors (See this list)
- Very Stable and very many releases with new features
- A lot of 3rd party options - both free and commercial
- Java based
- Free - If You can get a Community or Open Source License its free; the latter is actually giving access to must plugins for free also.
Why not to use Confluence?
- Not free - and even though license costs are low, it all add's up. Free alternatives are CMS'es like WordPress, Drupal ,Joomla or Liferay
- Requires quite a lot of resources (it's java....)
- The Download version requires direct server access (Windows or Linux).; where as the Cloud version requires no local resources.
- Java based
Not free? Well, if You are a non-comercial organisation, Open Source Project or a private person - try to apply for a "Open Source License" at Atlassian
A nice starter package could be
- Confluence 10 User = $10
- RefinedWiki 10 User = $10 or Enterprise Theme 10 User =$10
= $20 / Year
Dowload or onDemand?
Cloud version
Plusses
Cheap and simple, but very limited towards plugins and manipulating on filelevel
Upgrades just "happens" without any effort put into it.
See the Plugin List here
Downsides
Blueprints cant be created
User Macros are not available
No control over upgrades (an be seen as a plus also 
)
Download
Plusses
Full flexability regarding OS and resources
OS must be maintained/upgraded
Upgrade paths/time are for selfdecision
Downsides
More Expensive
More Maintenance
When the decision is made for using Confluence :
If You want to control it Yourself, read the Confluence Install Cookbook
Secondly, I will recommend these plugins ( = Testet and/or tried and found very usefull):
| Type | Free | Commercial /Licensed | Comment |
|---|---|---|---|
| Content Enhancement | |||
| Theming | For alternatives, read Theme Plugins for Confluence | ||
| Drawing / Diagramming | Diagramly | Gliffy | |
| User Macro's | See User Macros | ||
| Misc | Bob Swift has some excellent Macro's at https://bobswift.atlassian.net/wiki/display/info/Information Also, these are typically quite cheap and does not follow the user-model for Confluence |
Both Adaptavist and ServiceRocket has a bundle of very nice and usefull free plugins