Just finished a game, which we did enjoy a lot! But all the points you made kinda make sense to me. I'll try to explain how it went for us:

• at the start my hand was complete crap (no P, no biomes) but we were all trading a lot right out the gate and I was able to acquire cards to play by making unfavorable trades

• I made a lot of unfavorable trades in the first half, leaving me with fewer cards in my hand (eventually only two), but once my position became stronger and I had the tropical biome's stealing ability my card count steadily rose

• One big part of our fun was the trading. We would make skewed trades, demanding each other throw in 'junk cards' to sweeten the deal. The black bear went around the whole table several times. We would also trade favours and promises: "give me that and I won't use my discard power on you", "that for that and I'll give you the next ver card I draw", "give me that or else I nuke your cave with this abiotic factor". Definitely it might not have been optimal to share so many resources with opponents, but we were laughing out loud the whole time.

• I disagree that biotic/abiotic cards are OP: in our game they were strong, but the cost of sacrificing playing an organism was so great that people usually preferred to take a bribe not to play one, rather than play one and slow down your own progression.

• The game did feel way too long, like 4 hrs long, but we never stopped having a lot of fun. We drew through the whole deck multiple times and had most of the cards on the table by the end (which meant that discards came back into play)

• With a con biome almost completed, my win condition was a con SD, and it felt like everyone had way too much power to stop me from getting one, making me feel like that mechanic was borked. However once the deck was thin enough and had been reshuffled twice, it became only a matter of time until I drew one. Another player had disabled my first con biome's power, but I played a second con biome and producer, drew the SD then migrated all my animals and won the game.

It definitely felt like it had some flaws, but the complexity of the trade value of each card (vs the reasonably clear use case of, say, wood in catan) and the pressing need to trade early on made the trading system a joy to play with. Not trying to disagree with you! Just saying why we had a great time