@OP: Well, history terrifies me when it comes to any Meet the Technologically Advantaged Neighbor scenario wherein you are not the technologically advantaged neighbor, so as a matter of survival it makes sense to do everything in your power to ensure you are the biggest fish or preferably the ONLY fish. To that end, I suspect my first run through will make the Emperor proud... Besides, starfish aliens just don't appeal, though I'd happily play a genetically re-engineered Terran offshoot.
After that, I think it'd be awesome to test the engine's capacity for negligent precursors. Step one, establish galactic government. Step two, scatter some robots, genetically engineered super-species. Step 3, engineer a catastrohpic collapse of society and watch as your children fall upon themselves in your sudden absence.
The only other animal that sweats is the horse
This myth wont die

. No, sweating is not unique to Humans, we're just
really good at it. If dogs couldn't sweat, then why exactly do you think they smell so... pleasant in the heat of summer? Most mamals can sweat, just not nearly as much as humans do.
And yet we're always the jack-of-all-trades because people always approach it from the standpoint of "humans are the only example of a sapient race we have, so let's make everyone else start off with the same template".
Plenty of species have sapience, we just refuse to acknowledge it because of the unfortunate implications. It's also hard to quantify, and there is no objective "line" that can be drawn between the rudimentary sapience of some animals and the anthropocentrically "complete" sapience of others (namely humans).
But yeah, I otherwise agree, that's why we are always "the middle," it's literally anthropocentrism. I always like to imagine humans as skirting the edge of the irrelevance/self-termination scale: at the far end, you have societies or species which are so "good" or "passive" that they never develop the impetus to advance into a starfaring race vs the other end where societies or species are so"bad" that they wipe themselves out before being able to reach the stars. I see humans as right on the edge of self destruction rather than some "middle" race. Remember, we reached for the stars... because it was a good way to drop nukes on each other and/or to pretend we weren't developing better ways to drop nukes on each other...
To our credit, it makes us monsters whom the rest of the universe would do well not to agitate

, provided their technological edge isn't overwhelming.
Woe betide the universe should some alien come and drop a bunch of tech on us...