In my Galaxies story, compared to the average alien species out there, things humans have going for them:
They're rather small and yet completely self-contained, making transport easy.
They're fairly hardy and medical manipulation is pretty easy, though this is partially because a lot of research has been done on them.
They can stomach a wide variety of living (dead/cooked) carbon-based species, and some that aren't.
Their energy inputs are mostly water and oxygen and misc nutrients that aren't so hard to come by.
Can perceive many colors and have good visual accuracy, depth, and visual memory.
Fairly quick learners and good memories. Very curious.
Departments humans are lacking in:
They can only tolerate a very limited range of temperatures and environmental gases without external or internal modification.
Their hearing's not so good, and their smell is abysmal, so they can't perceive a lot of communication in intergalactic dialogues.
Very very social creatures, do not do well in isolation. Do limitedly well with only aliens and no other humans.
Apt to form cultures very quickly even if said culture is detrimental to some lifeforms, including other humans.
Capable of dying extremely rapidly, short lifespans in general, not very durable.
Reproduction is inconvenient and cannot reproduce asexually or remotely without assistance. Concept of gene pool can be problematic.