Going by this week's denotes, it looks like the tech tree is going to be somewhat altered in the way that progression happens. Something that I feel could added, and that would work extremely well with contracts, would be the inclusion of a system that unlocks tech nodes based on in-game accomplishments, meaning that a particular engine or part can only be unlocked once the player has done a specific experiment on a specific body. Like, for example, Nuclear Engines can only be researched after one has sent a probe to Eve. Or Mainsails can only be unlocked after one has recovered a surface sample from Duna. Or larger docking nodes can only be unlocked once the player has completed an orbital rendezvous. This is marginally more realistic than the current system, and would encourage players to progressively explore rather than grind for science on Minmus to get most of the parts that they want.