Thanks for the feedback. Monitoring forums like this (and other fan sites) is one of the primary avenues of feedback we use when deciding what changes we may make for future patches. Clear and concise feedback and lists of issues are definitely most useful to us. The more objective specifics you can provide, the better.
As mentioned in this thread, you should be able to rename triggers and create new trigger groups fine; I'm not quite entirely sure what problems you are encountering. Similarly, there are numerous mechanisms for activating triggers from other triggers; the game's campaign uses this, and the Play Dialog trigger, extensively, so I'm not sure what problems you are encountering.
Units and animations in the scenario editor that do not necessarily have their full sets of animatons are there because we figured it was better to provide more "raw" units for scenario designers to work with. We are continually amazed at what you guys manage to do with the source materials we provide!
For Diplomacy, remember that you have to set the diplomacy from both directions -- that is, just because player A is an ally to B does not automatically make B allied to A.
As for unit and name editing of specific units; this was a feature that got cut relatively late in the project and thus is not currently a supported feature of AOM. It is very good to get feedback from y'all about what additional tools in the scenario editor you would find most useful (such as being able to edit names).
Thanks again for the feedback; please rest assured that supporting the users who generate such great content for the community like custom scenarios and random maps is very important to us.
-- Rob "Xemu" Fermier
Lead Programmer, Ensemble Studios