Testing
A lot is to be said for "testing" an arc, First off there is no incentive to test or help test an arc for someone. Its damn hard to get a team together and most people temp-publish it anyway so people will join then remove/edit. Perhaps some ticket reward or alternative incentive to test arcs.
Testing tools:
Since the point of testing an arc is to see if particular features work, it would benefit (especially those that cant find a team to help run thought a 5 mission arc just to test the end) to have in the architect options something along the lines of complete all objectives, complete "rescue" objective etc. Note that for obvious reasons any badges associated with completing an objective would not be awarded for the forced completion. Maybe even a force mission completion would be suffice. (perhaps similar to the force mission completion we have on mission contacts)
Trigger restrictions: This is one thing i'm a little disappointed in. When i heard of the Ma system i imagined that there would be a lot more in terms of triggering. If your unfamiliar with what i mean it's (in this case) the condition that is required for an objective to be created. eg. Boss at 1/2 health -> Ambush the boss would be the condition of the trigger. Including this the only other option is "Objective: completed"
What i would like to see is more control over when things like this would happen. For example adding multiple triggers, At the moment you can barely create a chain of events. (in fact last time i tried it give me the loop error despite after multiple checks it was a chain).
Objectives Suggestion
Defeat * enemies (eg. Defeat 50 Longbow): This one could be difficult in terms of the difference in solo and group play. (The number would have to be flexible for this to be implemented) - Taken from Cimerora TF final mission
Clear ambush: I'm not sure i have to check this one but as far as i know ambushes cannot be set as required objectives, in situations where you are ambushed it would be nice to add, like a villain bank mission, defeat $enemy to escape. (:
Talk mission - Allow a "Person" to be inserted into a mission like a talk. You dont have to interact like a normal talk contact but atleast click -> speak type thing to allow dialogue to be spoken. Currently theres no decent way to insert a person you have to speak with without having to rescue them. And into that they can only speak a few words of dialogue. (please allow a decent size dialogue text space for the "Person")
Additional:
Double missions - Being able to force the player to go from one mission two another, like a two part mission. An example of this would be. mission 1: Travel to place a using device 1. (click objective complete requirement) once finished it sends you to the next map which is really part 2. which would remove leaving the area and the middle part of talking to contact etc.
Obviously restrictions would have to be put on these to be able to make them work but i can at the moment see no way these could be exploited other than adding features for those who want to use this system to create decent exciting stories.
Edit: Small edited addition... Make it possible to add a "Hero" Instead of always being an AV.