To expand on this further: Make it a string of content to balance it out with the usually longer SFs/TFs. (I.E. Part 1, Part 2, etc).
Or a definite 5-story arc with medium-long missions.
You're right, although I guess I didn't really elaborate upon this point, since each arc would have to be hand picked by a Dev each time, I guess I just assumed they wouldn't chose a one mission arc on the smallest map with no foes and the only objective was to click a single blinkie.
Although, I suppose the Devs could work out some sort of informal scaling reward, the longer the arc, the more rewards at the end? Perhaps a minimum limit of 2 or 3 missions, with the max being 5 of course.
Off the top of my head something like:
1 mission arc = Chance for shards to drop off of mobs like in all other content + a few threads
2 mission arc = Shards + a few threads + 1 Astral
3 mission arc = Shards + a few threads + 1 Astral + Drop of Well
4 mission arc = Shards + a few threads + 1 Astral + Drop of Well + 1 Empyrean
5 mission arc = Shards + a few threads + 1 Astral + Drop of Well + 1 Empyrean + 1 random iSalvage
Mind you, since the Devs have to hand pick the arcs, one of their goals is to pick arcs that make good use of the AE system to create challenging fights, either by using existing mobs or creating mobs that you can't just steamroll through easily. For the average pug at least, some super teams will be able to steamroll though just about anything like they do now, but that's another ball of wax. 
Perhaps they could hold a weekly (or monthly) contest where they would create a thread and let the player population sift through the many arcs and vote on a top ten or so, then the Devs would just run through those 10 (instead of hundreds) and select one from that much smaller, more refined, pool of content. Then the process would repeat again next week (or month).
Just to be clear, each time an arc is picked it gets added to the pool of AE incarnate arcs that are available, so that over time they will be able to build up a huge number of arcs that can be selected along side of whatever the WST is for that week.
One thing I'm on the fence about: Understanding that the drop of the well reward is a one time reward for that week, just how it works now. Part of me thinks that the rest of the rewards should be given each time you complete that arc, the other part of me thinks that there might be some player backlash at that and I might suggest also making the other rewards a one time gain, so at most you could gain them ONCE each week. I.E. 1 Astral, 1 Empyrean, 1 random iSalvage per week. This would eliminate any possibility of anyone farming them, not that they would be a good way to farm for those rewards at one of each at the end of an arc. At that point, it would be much more efficient to run a real iTrial instead.
"All that crap is grey to me, no XP." - Positron 5/15/05 8:36am . . . The world stopped and silence ensued except for the sound of a crying infant off in the distance.
"Everyone needs to chill the hell out." - BackAlleyBrawler 11/13/08 3:26pm . . . Geeks around the world stopped and blinked.
Are they even still selecting new Dev's Choice arcs? Last I heard that had been abandoned.
"You don't lose levels. You don't have equipment to wear out, repair, or lose, or that anyone can steal from you. About the only thing lighter than debt they could do is have an NPC walk by, point and laugh before you can go to the hospital or base." -Memphis_Bill
We will honor the past, and fight to the last, it will be a good way to die...
I don't honestly know. 
But I have to believe it would be much easier for the Devs to run through a few AE arcs a month and pick a good one (or several) than it would be for them to create from scratch a traditional content publish of the same length.
"All that crap is grey to me, no XP." - Positron 5/15/05 8:36am . . . The world stopped and silence ensued except for the sound of a crying infant off in the distance.
"Everyone needs to chill the hell out." - BackAlleyBrawler 11/13/08 3:26pm . . . Geeks around the world stopped and blinked.
I was thinking perhaps that the Devs could over time pick some good Canon oriented arcs and toss one each week into the WST pool, "not in place of", but rather "along with".
You wouldn't earn two rewards, but it would be another alternative to whatever the current WST is, especially if it happens to be one you don't like very much.
It would be a source of near infinite content for the Devs to draw from, also it might spark some more interest in the AE system, all of which are good things.
If this takes off and works out well, the Devs could consider expanding it to also reward Incarnate drops, not many of course, we wouldn't want it to become a superior way to earn those things, but more like an Xmas stocking stuffer, nothing you really need, but a nice surprise when you get it.
To be clear, the arcs would work similar to the other Dev choice arcs, once they pick an arc, it remains locked and can't be altered to prevent exploits etc. Ideally the Devs would pick arcs with challenging opponents and missions, and even more difficult ones for Incarnate reward arcs.
Anyhow, was a simple suggestion that crossed my mind recently, figured I would share.
Thanks for reading.
"All that crap is grey to me, no XP." - Positron 5/15/05 8:36am . . . The world stopped and silence ensued except for the sound of a crying infant off in the distance.
"Everyone needs to chill the hell out." - BackAlleyBrawler 11/13/08 3:26pm . . . Geeks around the world stopped and blinked.