- Tomestones are found in relatively the same quantities from all the same locations as always, but the lower tier is now Soldiery and the upper tier is Poetics. Dungeons that used to give myth will now give similar amounts of soldiery, for example.
- Alexandrite can be gotten once/day, and additional Alexandrite has a chance to drop on completion of any FATE while wielding Animus/Novus/Nexus. Finally, you can exchange Allied Seals for Alexandrite at your Grand Company.
- Allied Seals are a currency from Hunts: Hunts involve open-world boss-class monsters that can spawn in many different zones. You can examine the Hunt Billboard at your Grand Company for daily/weekly marks that provide seals, or participate with other players in locating A and S rank marks, which have longer spawn timers and provide Allied Seal rewards on every kill.
- Sands/Oils can drop in Second Coil and Syrcus Tower, and you can also exchange Allied Seals for Blood-spattered Mark Logs at your Grand Company. These Logs can then be exchanged (2 for an Oil, 3 for a Sands) to Aelina in Mor Dhona.
- Nexus upgrade involves using your Novus and running many many dungeons/raids/trials in order to generate 'Light' within it. Different duties provide different quantities of light, and every hour there will be a particular set of duties that give bonus lights for that hour. People collaborate on these boards/reddit/party finder/etc. to determine which duty has bonus lights at a given time; there will often be a Light farming party in Party Finder. The Nexus upgrade increases Novus from iLevel 110 to 115, with respective increases to weapon damage/primary/secondary stats.
- Each patch that provides higher iLvl will make doing Primals easier, but in general yes it's tougher to do them through Duty Finder rather than Party Finder.
- Savage Coil is an upgraded version of Second Coil wherein all the bosses are tuned to a MUCH higher difficulty. The normal rewards from Second Coil do not drop; the reward for completing each Turn is an achievement and a related title.
- Take the time to skim/read the 2.3, 2.35, 2.38, and of course 2.4 patch notes. It's a lot, I know, but it will really help you get a better grasp on what has changed that I didn't mention here.