Of course, I have no idea but my hunch is that aliens (the sentient ones) might be rather boring in case they are capable to visit us. As soon as technology overtakes the intellectual capabilities of the ones who have created it, the bottleneck for the pressure to be innovative opens completely. This has the consequence that intelligence is no longer a preferred or necessary feature to survive, on which other features are emphasized like the looks or the likeability.

Since it needs very sophisticated technology for interstellar travel, I would say every alien civilization must have passed this threshold. This means, they all will be looking more or less alike (given the natural beauty optimum), they will also be very polite and perhaps a bit reluctant and they will also be very equal in their intelligence. But the intelligence itself will be rather average or as good as it needs to be to communicate with their machines.