Tips zenith

You usually want to win by gaining 4 planets. Going for 3 of the same make you vulnerable as soon as you get the second token (since the token come back to the middle). Going for 5 is more expensive.

In technology, you usually want to focus on one specific path. After the third level, it start to be really good. The transfer 3 cards is great, especially early since you will be able to steal 9 cards across the whole game. The +20 silver (so used twice) can resolve your problem of silver for the game.

At 2 players, especially if you lack of silver or if you are behind in cards played, as soon as the leader token is on play, you should take it back immediately by using Diplomacy. The mobilise 2 cards look the best one early on, followed by the +1 Zenithium.

Early on, using diplomacy on mobilise 2 cards is good, you can think of it as a 'don't get +1 influence. Gain +0.4 silver with upside per turn'. Over 60 turns, that will be +12 silver (+6 silver compared to a 0 cost card).