"Can't you release an Alpha/Lite version of Honorbuddy?"
There is no such thing as a "lite" version of Honorbuddy. Addressing new content is trivial compared to the other work that must be done.
The vast bulk of the time is spent:
Reconstituting changes to the WoWclient object model
This is caused by changes in game mechanics--not "new content". The game mechanics deal with things like how spells work (overrides vs normal), active auras that are now passive or vice versa, changes to talent trees or skills, etc.
Dealing with refactored information.
Information that used to exist in one object has been shuffled to another object, or sometimes broken into pieces and scattered to several objects. This new refactoring must be analyzed and accommodated.
Analyzing and defeating the anti-botting measures Bliz had put in place.
(aka, "The Warden", now 'with friends')
Your client-side botting safety is the primary concern--a shortcut here would be devastating to the entire Community.
Many, many more issues along these line.
Almost everything else is trivial in comparison. The time it takes to produce a 'lite' version is virtually the same it takes to produce a 'full' version. Thus, there is no such thing as a "lite" version.