The goal, I feel, l for awhile now in Stellaris has been to flesh out the game and make it feel more alive. Paradox Interactive has the content and the mechanics down by now, so all we're really waiting on is that 'living galaxy' aspect that is so crucial to making the turn from a good game into a great game. To that end, the upcoming Banks update plans on bringing several things to the table to make that dream a reality, some of which we've already talked about.
The Banks update promises two new mechanics in particular that look very promising, and reminiscent of Europa Universalis IV's idea groups. The Tradition mechanics, or 'trees,' are broken into seven sub-categories, and each of these trees has a starter bonus, five unlockable bonuses and one last bonus that is gained once you've unlocked the entire tree. These traditions are unlocked with a brand new resource, Unity. Unity is an accumulative resource that increases each month like Influence, but Unity is gained through the construction of government buildings like temples and monuments, not administrative centers. The five Tradition trees that will be available are:
Expansion: Focuses on growth through rapid colonization.
Domination: Focuses on maintaining control over your population and subjects.
Prosperity: Focuses on economic growth.
Harmony: Focuses on maintaining a happy and diverse population.
Supremacy: Focuses on growth through military conquest.
Purity: Focuses on strength through homogenity and dominion over other species.
Exploration: Focuses on exploration and scientific discovery.
But you won't be able to access all of these right off the bat at the games start. The cost depends on the size of your empire and how stable it is. Unhappy factions, slaves, and pops apart of a minority species all increase the cost of a Tradition, but you can avoid this by adopting the right Tradition at the right time, dramatically upsetting the current balance of power between ethics and pops in your empire.
There's unfortunately still no word when Banks will be released, and the crew working on the game is currently on Christmas Break until January 12th, so I can't tell you when we can expect to see these changes implemented but I'd imagine they're coming sooner than you'd think.