Arcee has shown to be very kind, loyal, respectful, caring, calm (most of the time), and quite friendly towards her allies. When Arcee was trapped in the Arctic with Optimus, she suggested that they play a game called "who screwed things up back at base." This indicates that she knows how to make the most out of situations. When they were close to dying, Arcee placed her left hand to hold on Optimus' left hand as they accepted their fates.
This also shows that she can be very warm hearted