(time pressed to go line by line)
Yeah and there is quite a bit to find too.
Flexible Casting
You can use your sorcery points to gain additional spell slots, or sacrifice spell slots to gain additional sorcery points. You learn other ways to use your sorcery points as you reach higher levels.
Flexible Casting (p. 101). The created spell slots vanish at the end of a long rest.
A long rest is never mandatory, but going without sleep does have its consequences. If you want to account for the effects of sleep deprivation on characters and creatures, use these rules.
Aspect of the Moon
Prerequisite: Pact of the Tome feature You no longer need to sleep and can’t be forced to sleep by any means. To gain the benefits of a long rest, you can spend all 8 hours doing light activity, such as reading your Book of Shadows and keeping watch.
S Hogarth: is there a hard limit on how many short rests players can take per day, or purely up for the DM to decide?
Jeremy Crawford: Limits on short rests: the number of hours available, time pressures in the story, and monsters interrupting.
Igor Ruffinengo: Howdy, Mike! Just one question: can I start a short rest while keeping concentration on a spell like Hex? Thank you!
Mike Mearls: as long as you don't sleep
tl;dr: While everyone else sleeps to replenish their stuff you complete two short rests to bank limitless extra Spell Slots which are never wiped and it doesn't even break your Concentration.
Also a couple of shout outs since I've been reading into it some. With the new Druid option Circle of the Shepard a you can add your Druid level to Goodberry healing for a limited time as a nice counter to Life Clerics stealing it. Gloom Stalker Rangers / Fighters can Action Surge during the first round of combat and gain two additional attacks with an extra +1d8 damage too which makes it better than Abucascade or w/e from the UA's Ranger Alt for burst damage. But if you want something longer, Monster Slayer's +1d6 stacks with Hunter's Mark and it's later obtained auto-Save is nice. The Sorcerer's Divine Soul gives you full access to the Cleric's Spell List and one extra Spell Known which is why people keep talking about it too.
Feat wise, Prodigy deserves a mention. You gain a Language then one Tool & Skill Proficiency then you can choose one Skill to gain double Proficiency. It's a great way for any Class/Path to access Expertise without having to multiclass out before they would want to. Flame of Phlegethos I'd
almost consider too, +1 Cha or Int plus if you spam Green-Flame Blade you get to reroll 1s and your opponents take an extra 1d4 damage each time they melee you which isn't bad but there are better Feats to take.
Spells, so many to talk about. Adsorb Elements is Reaction-based so you can Concentrate on something else while enjoying Resistance vs your enemy's nuke. For 25gp plus 25gp per seven days Ceremony can give you a stacking +2 bonus to AC so long as your spouse is dead. Twinned Dragon's Breath on you and your friend's mount is a really easy way to mop up trash. Wizard(necromancer) 10 / Warlock 3 can use Create Homunculus to create a creature with no HP penalty because you prevent it from happening rather than recovering it. And speaking of undead, Danse Macabre is Animate Dead on crack trading around for an hour long duration and uses your Concentration but it can animate up to thirteen undead minions (with mods to att/dmg) using a single Action making it viable to reanimate recently slain foes to turn the tide of the current Encounter. Guardian of Nature is lesser Tenser's with it's defensive option giving you 10 temp HP, Advantage with Shillelagh Attacks, an Advantage on Constitution Saves, and everyone nearby moves at half speed. I love Mighty Fortress because it's week long castle filled with food & servants plus I simply like the idea of it (plus the doors in & out are optional). Temple is the divine version and buffs out a little more too but only lasts for a day making it harder to leave a trail of decaying castles behind you. Shadow of Moil is also a quick way to gain an Advantage on attacks against Humans while punishing them with Disadvantage and 2d8 retaliation but far to many things have darkvision for it to be too useful and Xanathar even jokes about this in one of the notes. Soul Cage gives Wizards a way to heal up to 12d6 damage per 6th level Slot among other things like Scrying or Advantages on Saves off a single Spell. Tiny Servant is a useful trap finder that can double down with the Druid's Animal Shapes for a bunch of HP fodder and Wrath of Nature is pretty nice once you realize all four effects can happen to the same target every round.
Find Greater Steed is right up there with Shadow Blade too. Like Find Steed it gains any Self-only buff you use like Crown of Stars and Shield but it includes a couple flying options with 10s for Int scores giving you some nice kiting support that's capable of acting on it's own if needed.