You start a new game, the galaxy map is vast. Races could be anywhere, decent planets could be anywhere. There is a real sense of exploration and discovery, you don't know what you're going to come across, or when. Depending on the size of the map, a game can take quite a while, space 4x at its best.
Unfortunately, the technology tree is entirely predictable. There is no sense of discovery whatsoever. This is common in games, tech trees might be unique per species, but the same every game. I think there is a need for a technology randomiser, or attribute randomiser. So for example, let's consider researching Beam Weapons:
1. Choice - Research Beam Weapons
2. Choice - Prioritise a)power, b)range, c)mass, etc. etc.
3. I select a) power
4. Research begins,... tick tock...
5. Success, I discover a new Beam Weapon with a randomly assigned name, and attributes randomly assigned within a predefined range. I prioritised a) power, so the attribute range should have some preference multiplier to ensure I advance this attribute. Other attributes should return within the attribute range previously discovered.
In this way, technology trees can be unique to each race, AND unique to each game. It will also allow technology trees to last longer! No longer will the Doom Ray be the ultimate beam weapon, we can keep researching! This would make research much more interesting and open up all kinds of strategic options. This same principle could be applied to all kinds of technology. It doesn't mean we can't still have race unique technologies. It just changes the way we research, and what we find.
The point is that research and technology should be a discovery, in the same way exploring the galaxy is. A predictable tree spoils that sense of discovery.