Harmonies is one of those games where colors and design make you forget about the animosity toward others (except in one on one, where "stealing" animals is fair game). The frustration of not always being able to choose the best animal is probably the inherent challenge of this game. So you rattle your brain and try to find what fits, rather than waiting for the best to no avail. There is no time to be mad at somebody else, so in the end, you force that frustration upon yourself to make your brain imagine the patterns faster.
I've heard many people saying the game is nicely balanced and I do agree to a certain extend, especially when playing without Spirits. It is nice, easy and full of possibilities. Final scores are generally off by 10 points max... I will not cover the animals because they do a fine job on their own.
However, it feels like a total different story when Spirits are involved. Those cards are the ones I hear people complain about imbalance, and after 50 games I can say I already have favorites. I Shouldn't (they are all so cute). But for the sake of argument, please, give your opinion upon your favorites in rising order like so:
Red
Those two I find hard use to their full potential. Tall builds take more time and it is often disappointing to end the game with unfinished houses.
The
Stork seems the most imbalanced. 6 points compared to the 4 point of the Cat or the 7 of the Dragonfly... 8 or 9 points feels more like what it should be.
The
Cat seems easier to use as it allows a more forgiving spread on the board.
Green /
Grey
Those two families have approximately the same cards.
The mononoke
Stag (Anybody also thinking this is the most beautiful card in the whole box???

) and the
Ibex require you to build tall, and again, this type of play is time consuming and token consuming with the fear of not being able to finish what has been started.
The
Owl and the
Groundhog are in my experience more flexible. Filling your board with single-tokens at 3 points each is way stronger than building tall. In Harmonies, who controls the timing of the end-game is the alpha of the table. Being able to scatter "pieces of junk" to fill the board faster AND being paid for it, is a real advantage!
Blue
Water tiles don't stack. This makes this style of play faster than the previous colors. Fast end-game is advantage play in Harmonies!
So the
Turtle is actually a fast(er) animal in this game

. This card is simply good by itself anytime and works wonders with the long rivers it is often the source of.
The
Dragonfly, on the other hand, is OP, trading a river for 2token-ponds. Again, this card plays into the "scattering junk is rewarding" mentality. Where reds, greens and greys have a high average of 18 to 24 points when played properly (over 12 tokens / 4 turns), the Dragonfly blasts 21 points (over 6 tokens / 2turns). I cannot stress how strong I think this is ... "for single-token / pieces of junk".
Yellow
Another family with opposite play style and non-stackable tiles.
The
Lion. The reason why we return to that warm-colored box when friends pass by. Similar to the turtle in its layout, its 10 point goal is appealing to most, who imagine it multiplied by 3 from the start of the game. (Un)fortunately, this card teaches us that sometimes life has other plans, but if completed with 2 or 3 smaller fields, leaves us fulfilled like an intermittent sunny day.
The
Butterfly...is just dope with wings (the last witch hunter feat. Vin Diesel). With a top average of 7 or 8 single-tokens scatter all over the board, this card will earn you 35 to 40 point on its own. Couple it with the ladybug / the meerkat and you have an effective scatter play that will draw the end of the game extremely fast. Granted, this strategy won't earn you the most point, but it doesn't matter as you watch your opponents board half empty desperately trying to wrap things up. This is THE Spirit, the first-pick, the errata anxious card. It is beautiful and deadly!
To sum up:
We all want to build grandiose boards, finish that fish or rabbit card... but in Harmonies, it seems that smaller is better.
This is not too prevalent in the original game, as the frustration of the selection will see most people take bigger animals and work with what is given. This is the well balanced version of Harmonies.
Playing with Spirits guides us into a rabbit hole that we, sometimes, don't want. I've seen many players commit to building a Spirit, just to be crushed by the lack of corresponding tokens available to them. If only they hadn't played that Spirit...
And this is maybe the only answer to the imbalance felt by some of you... If confronted with two uncomfortable choices in Spirits, pick the least bad and maybe just don't play it...
Don't give that Spirit the satisfaction of being a pain in the ass and fight to get the animals that give you peace of mind and harmony.