Help please: Assessment Engine Needed

I have had multiple meetings this week around the topic of online assessments. Much to my surprise (well, not really), it looks like there is a lot of passion behind creating, hosting, and using assessments effectively. The needs of our district, as far as I can tell, are to have a single place to create all assessment items, tag these items with “essential learnings”, create sophisticated assessment banks,  administer them as best practice for interim assessments, and have all of the scores from these assessments feed into our Infinite Campus (our information management system). No small task.

However, I don’t have a good answer for this issue, mostly because online assessments have always been a pretty dry topic to me. My orientation is to do nearly all assessments as a part of an online project, something that is more authentic than a question bank can hold. So, here are the options that I have delved into so far:

1. http://hotpot.uvic.ca/ – Hot potatoes seems to be a very simple way to create and host assessments, but this needs to be held somewhere and it doesn’t allow for a lot of tagging or reporting as a native format.
2. Moodle Quizzes – The built in Moodle Quizzes are pretty robust, but they do not seem to be that portable outside of moodle, and I do not see the ability to categorize all questions and assessments as a part of a greater organization. Putting these together with Infinite Campus looks like it could be done with some integration, but I don’t think that it is worth it if the assessments can’t be analyzed for effectiveness and tagged with many different sorting abilities. (Although the tagging does look like it is coming in 2.0)
3. Ed Mastery (Seriously, this is the best link I could find) – This is the proprietary solution that our online school will be using because more than half of the assessments are already stored there. It has a lot of the functionality that we need, but it is somewhat of an unknown because the company does not have a community of users (as far as I can tell). And, it will have a license fee per student.
4. http://www.qtitools.org/ – This looks super promising in terms of getting all of the information created, stored, accessed, and assessed. However, it looks hard. I’m not sure that the majority of the people creating assessments would be able to tackle it.

So, the help I need is this:

Do you know of any other Assessment Engine that is out there that will cover all of the bases that I need? What direction should I bee looking in to make sure that I am researching every possible angle.