I end up with something between tech as described in the books and "basically today with a few 'sci-fi' techs thrown in." (reactionless drives, jump drives, fusion, gravitics, &c.)
On the one hand, I'm more interested in gaming than being realistic. In many ways, my D&D world a modern world with medieval/fantasy window-dressing. My TU is really the modern world with sci-fi window-dressing. In the end, that's all we (my group) really want for a game.
& I'm too lazy to update any of the mechanics. & Heck, if your universe is only 2D anyway...
On the other hand: I'm a firm believer that the more things change, the more they stay the same. The "futurists" who try to predict what realistic future tech often get it very, very wrong.
AI never reached the goal the futurists put on it (full human-like machine intelligence), but it has spawned lots of good tech. VR never reached the goal the futurists put on it, but it has spawned lots of good tech.
The futurists then write these things off as failed because they set unreasonable goals with short-sighted timelines. AI & VR might still realize those goals, but--if so--they're a long way off.
Now, it's nanotech. Nanotech isn't ever going to do the things the futurists envision. At least not until long after the futurists have written it off as failed & forgotten about it.
Then there was the whole convergence thing. The futurists were smart enough to see that the technologies were converging, but they couldn't understand that there's a limit to how much use patterns would converge.
I wouldn't be surprised if in the the 1100 year of the Imperium there are things that don't operate all that different from TVs & phones today. I won't be surprised if some form of slugthrower is still the preferred weapon. I won't be surprised if many people still study unarmed combat & melee weapons.
Oops--got a little ranty there. Again: Playability. Basically today with sci-fi dressing. Don't want to bother with changing mechanics.