Okey going by each of the minifigures:
Shark Army Octopus - aka Orange Squidward
An army builder figure, if you really want a fish related army, his octopuss headgear looks very usable even as a separate thing by itself (unless the shoulder piece is attached with the headgear, then its gutter trash), but overal with common weapons such as the shooter, fish and the common print, this figure will be one of those that most people will try to avoid as much as possible.
Zane - aka Happy Civilian Zane
A cheap way to get the Zane minifigure and his exclusive new hair piece in white. His expression is appropriate and reusable even outside of Ninjago. Heck, a useful figure for any type of collection. He has the camper backpack in new colors, and has very nice torso and leg printings. His torso print has an easter egg in a form of the Alien Conquest head leaches.
Overall a very useful figure and a desirable one.
Cole - aka Teen rock edgelord civillian Cole
Now this one is going to be very useful. He has that new hair, but this time without a scarf going over it, which makes it even more useful for regular use. His rock oriented torso print is nice as well as the leg printing (though the legs are probably only usable with any top torso thats primarily a shirt in dark blue color) . He also has a descent accessory of a jukebox in a black color.
Very useful for any use, also very desirable.
Shark Army Angler - Female Ripjaws.
Hoboy, its a lady, a lady fish, with hyno eyes and a fish mallet. Now this is what makes me hope that the shoulder piece is a completely sepparate thing from the headgear a bit more than before since its obvious that the headgear is not attached to the shoulder piece. It also is a nice army builder set and a nice way to get female version of that army torso print. Her accesory is somewhat meh like the ones before. The head printing maybe the most useful thing on this set for outside use.
Overall a bit more desirable than Orange Squidward, but still one of those you hope not to get in blind picks over so many other useful choices.
GPL Tech - aka Robins Girlfriend
What a very very nice and highly useful figure for sciency stuff. It has the lab coat but with the awesome batman shirt under it. Has that goofy head print that stares deeply into your soul (looks like she is a Faculty student by the looks of her dead eyes). Her accesory is a standard mug, and a amazing laptop set (apparently screw over Apple, LEGO is the new and hot electronic brand on the market)
This maybe a way they tie in LEGO Batman with Ninjago (more on the connections later on).
Very desirable figure, want it myself cause of the lab coat.
Kendo Kai - aka Kendo Edgelord V2.0
A nice addition to the kendo club with the Kendo headgear and shoulder pieces colored in black and red with a bit of pearl gold. Nice way to get the Kai hair piece, and hte expression is so Kai.
Overal a nice addition to the Ninjago collection, but not as useful for everyday use aside from the hair and maybe even the head.
Flashback Garmadon - aka Trump Garmadon
Wow Misako, what ever did you see in this dude, cause it sure wasnt his looks.Jokes aside this is a very goofy rendition of Garmadon with a useful Trump hair piece and accesories. Not as useful of a torso print due to the nature of Garmatrumps design, but the legs are still servicable.
A funny figure, will be desirable just for the goofy factor and for all those potential Trump figures, but not as many useful everyday pieces besides legs, hair and accesories (which aint anything new).
Garmadon - aka No cloth Armored Garmadon
Easy way to get Garmadon in his battle clothes with those awesome new staff and hat pieces. Overal nice addition ot hte Garmadon collection, but not very useful for everyday use due to the very specific piece usage on him.
Llyod - aka Blueprint Le Lyod
Meh, bleh, already have bunch of sets with his Ninja attire. I guess this is a cheaper way to get the main character in his battle clothes, but appart from the head and blueprint em prints there is nothing new with him.
Overal average figure, been there done that.
N-POP Girl - aka superuu Ninjago POP Girl Sugoi uber Kawaii Unikitty Moi Moi uguuuuuu
Definitely a Unikitty fangirl, and definitelly envocing that Japanese street cosplay.
Her hair isnt anything new (Harleys hair) but now in cotton candy colors. Everything on her is useful for everyday use.
Very desirabel figure, super weeb kawaii.
Gong & Guitar Rocker - aka Coles favourite rock band
Another rocker in the minifigure series, but again very useful prints from the legs, to the arm tattoos, and the hippy hair in black.
Useful for everyday things, an average figure in terms of desirability.
Shark Army General #1 - aka Mermaid General
The first way we can obtain this figure with those very rad cloth pieces, and her torso print is also not too bad. The hair is an old piece but still very useful due to it this time being completely black. Her head print is useful for everday things and her milkshake accesory is a welcome addition to any collection.
Very desirable figure, lots of interesting pieces.
Shark Army Great White - aka Scorched Earth Black Shark General
Silly little figure with not many useful pieces for regular use, but still a nice addition to the fish army collection. also very silly flamethrower fish.
Jay Walker - aka Jay Let me take a selfy Skywalker
Useful figure all over the board. From the new hair piece, to the rad new scarf piece, he also has useful prints all over. And the ingenious way they made a selfy stick, brilliant.
Very desirable figure, everyone will want 10 of him.
Misako - aka Best LEGO Waifu
A cheap way to get Misako but with an all new exclusive workgear torso and leg prints. The new hair spaks for itsefl and her happy face is useful for any use.
Very desirable figure for any use.
Sushi Chef - aka Restaurant Pirate
Neat figure if you want to make a sushi joint. Sheap way to get the sushi pieces and the new chopping utensil. His torso print is useful overall and I can see his legs be used for a scientist figure and such (aka Dexter comes into mind)
Nice figure, desirable parts, but overall aveage by looks.
Lloyd Garmadon - aka Breakfast Le Lyod
This is the year for those that like green, have blonde hair, and like hoodies. That hoodie is a new and awesome mold that everyone will want, and those spoon nad bowl pieces with the oriental printing. Cant wait for the hoodie to come in more colors, overall useful figure and top tier desirable.
Spinjitzu Training Nya - aka rehash torso Nya
Meh bleh in terms of the whole body since we already have ways to get that in other sets, but again this is a cheap way to get this. Also very cheap way to get Nyas hair piece and her smug face is useful for everyday use. Also training wooden swords.
Desirable due ot her hair and head, bur average in terms of her whole package.
Master Wu - aka Breakfast Wu
Chicken wrecked Wu so much it had enough money to start a breakfast cereal company and now is rollling in the money. Wu can only smile in discontent of his loss (possibly contemplating jumping over another lavafall).
Not anything new when it comes to pieces, but still a cheap way to get Wu with new head print, and Breakfast prints will be desirable a lot.
Volcano Garmadon - aka Breakfast Garmadon
Again another silly Garmadon figure with additional sillyness. He really likes his volcanos (probably wants to chuck his loser brother over some lava fall due to his loss against a chicken). Nice way to get the bowl prints and pijamas. And a cheap way to get the Shogun headgear.
Desirable due to the useful prints and sillyness factor
Final verdict for the Minifigure series: 11/20 Slightly above average series but still with a lot of very useful pieces and figures. Would recommend it to any LEGO fan, even if they werent Ninjago fans to begin with.