As of version Neverwinter’s Swords of Chult the rough Astral Diamonds production is moved to a new system of random queues.
First of all let’s go through the different queues and discuss which characters should participate in them. All mentioned AD values include estimated non-VIP salvage values of runs as well. I have been very careful here. Especially in the epic queues you are probably able to get a bit more on average.
Any character above level 12 can already start participating in the normal dungeon random queue. It nets 8,800 AD. This should be one your daily list in terms of RAD production because it’s always super easy. At worst case you’ll get into one of the longer dungeons, but it’s only a matter of minutes to get through them anyway. Players can safely queue for this solo.
I would already compile a premade group for the skirmish queue (8,200 AD) though. The reason is that you can get into Illusionist’s Gambit, which in rare circumstances could end catastrophic if you’re in an undergeared group. Remember that this queue is available to all characters at level 64. So you’re not guaranteed to a full 70 party. The completion time really depends on the content, but on average this queue should probably take about ten minutes.
Now here comes the fun part. This can go from very quick (Shores of Tuern) to a true grind (Spellplague Caverns) for the 10,000 AD the queue hands out. If you’re solely behind daily RADs then you won’t be a happy fella landing inside mSP or FBI.
The rest of the list is easy to complete, but based on RADs per minute this is probably the worst queue.
I’m actually not sure how you should tackle this. I’ll probably avoid it as much as I can unless I really can live with going through Spellplague or Fangbreaker Island. In any case you should compile a party that can conveniently beat these dungeons. Nonetheless this is probably where we’ll see the most quits, leaver penalty or not.
Also premades might have a way to get around the longer dungeons anyway. The devs added a feature that allows groups to vote to abandon content. This is a great addition because it prevents situations where a minority of players hold the whole group hostage. However, if you communicate accepted content before runs and then just vote against everything else, it completely works against its purpose. I guess we’ll see.
The epic trial queue on preview currently doesn’t list Tiamat, but it’s probably supposed to be included. In any case make sure to build a potent premade that can beat Master Svardborg. Within a proper setup, the 8,000 AD from this queue should be fairly easy to obtain.