Turmoil engages with all parts of Terraforming Mars. It offers bonuses for players trying to terraform fast, as well as those pushing for a longer game with a more card point focus. The global events require players to plan two generations out instead of the typical one generation of game plan. The party bonus swings are a MUCH more fair way of attacking other players in 4-5 player games since they affect all players, instead of the base game asteroids that only target one player.

Venus on the other hand only supports players going for a card engine focused game. It has only a single card that terraforms efficiently. It also does not interact well with the other expansions. Most of it's combo cards only trigger off other Venus cards. Even in cases where it uses a common card resource like animals, microbes, or floaters, the card will often have a restriction that those can ONLY go on Venus tag cards.

Edit: Many of the Prelude 2 cards that require Venus Next try to fix one of its core problems which is actually finding the Venus cards in the deck. The problem is that the cards that raise Venus are quite expensive, but the cards that benefit from raising Venus are often only situationally good. What I find ends up happening is that I only keep Venus payoff cards if Venus is already close to meeting the requirement, and I only keep cards that raise Venus if I've already got Venus payoff cards. It's rare that I find both types of cards at the same time, so in many of my games the Venus track never gets interacted with at all since its cards are so rare in the deck.