I got my physical book last night. The store owner saved one of the special covers for me and each of the in-store DMs. The black and silver illithid looks really cool.
Some of the Conjure lines get more options from the book:
Cows are CR 1/4. If they move 20 ft. or more before attacking, their damage increases to 3d6+4. A stampede of cows can do a lot of damage and their attack roll bonus is a whopping +6, quite high for CR 1/4. Watch out for the druid on an open field. Watch out for the monk that stuns and then runs away before the druid has his cows stampede too.
Velociraptors are CR 1/4 (and tiny, more accurate to their size as archaeologists know today). They have similar stats to wolves, they have pack tactics, and multiattack. If you don't need the trip from the wolves, these are a bit more damage, though the cows will trump both if they can charge.
The Deinonychus is CR 1 and has a 3 hit multiattack WITH a pounce trait that can allow another bite as a bonus action after the trip. These are good as a conjured beast or as a wildshape at low levels.
Conjure Fey gets:
Annis Hag: decent bruiser, gets 3 attacks that have 3d6+5 damage or a single grapple that deals 9d6+5 recurring, has lowish HP but resistance to non-magical weapons, 3/day disguise self and fog cloud
Cast at level 7, Bheur Hag: not the greatest survivability but it has 1/day control weather, 3/day Cone of Cold, Ice Storm, and Wall of Ice, and At-will Hold Person and Ray of Frost. The 3 Cones of Cold would make it worth the slot IMO. Also has Maddening Feast which allows it to eat a corpse that died in the last minute and force an aoe incapacitating frighten effect
Cast at level 7, the Korred has a bonus action grapple/restrain. It can command a rope (and it always has a 50 ft. rope of its own hair) within 30 ft. to move up to 20 ft. to perform the grapple. It has a burrow speed, decent HP, resistance to non-magical weapons, at-will commune with nature, meld into stone, and stone shape, and 1/day each Conjure Elemental (6th level, galeb duhr, earth elemental, or xorn only), and Otto's Irresistible Dance. I cannot recall any rulings that a conjured being cannot itself conjure more creatures in 5e. A galeb duhr is basically worth 3 creatures, and Otto's Irresistible Dance is a killer spell too. If that wasn't enough, it attacks twice with a greatclub or by throwing rocks and does 2d8 extra damage per attack when touching the ground with a decent attack roll bonus.
Conjure Woodland Beings:
The Boggle is a CR 1/8 and has an amusing pseudo-grease ability or a sticky version that restrains. The DC is low but it's 8 of them, and you can choose to either go for Dex saves or Str saves depending on whether you're going for slippery or sticky. It also has bonus action 30 ft. teleports at-will essentially between doorways, arches, etc. from its ability to open dimensional rifts only it can use. Interestingly, just opening one of these rifts allows it to "flank" from 30 ft. for the purposes of stuff like sneak attack because it's considered to base things on either side of the rift when it's within 5 ft. It's worth looking into the intricacies of the ability to see what shenanigans it allows. The ability says the Boggle is the only thing that can use the rift, but it can push "anything" through the rift. You might be able to set up a short-range teleportation network for yourself with 8 of these.
CR 1/2 Darklings and CR 2 Darkling Elders have poor HP but they let out a 10 ft. radius blinding flash when they die. The Elder has decent damage that relies on it gaining advantage to get the full effect, and can innately cast Darkness once per rest.
The Meenlock is CR 2, has a fear aura, a recharge 5-6 30 ft. shadow teleport similar to the monk ability, and its claw attack has a low DC paralyze as a rider. Downside is it has light sensitivity and fairly low HP and attack roll modifier for something you'd get out of a level 4 spell.
Quicklings may or may not be worth mentioning, but they're CR 1 and have some interesting quirks. They have 120 ft. land speed, they're tiny, attack rolls have disadvantage on them unless they're incapacitated or restrained, and they have evasion. They have a high attack bonus and AC for a CR 1 but only 10 hit points. If someone in your party is denying reactions via something like Shocking Grasp or Open Palm Technique and you're not dealing with Con save aoes, these things could be really good as they go in and out of melee range.
The Flail Snail is a CR 3 elemental for people who want cool points with their elemental summons. Despite only being available to Conjure Elemental, which will only give you 1 creature regardless of CR, the Scintillating Shell ability might be worth it for the DC 15 Wisdom 30 ft. radius stun attached and it has some strong anti-caster traits.
There's nothing to report for Conjure Celestials or Conjure Minor Elementals.