Gamora give him a look that communicates he said the right thing. They know of their deeds, but these Avengers are a mystery. The burden of proof is on them. She privately agrees they do seem to be making a strong first impression. Considering how useful Peter has been as a leader, faults and all, she's willing to accept these people could be help too. It certainly helps they accomplished something not even her people could. As much as it hurts to admit that even privately, the people of Terra must be formidable to do so much.

"We have enough allies." She points out despite knowing there's no such thing against Thanos. Even so she wants to add onto the pressure.