Dorothy:
I'm wondering if the "cricket" sound you're hearing is their normal chirping sound? We've had a few who get a bit chatty. The sound they make sounds sort of like crickets. They aren't very loud, so you ned to be close to hear them. We have one that sits on the feeder & with each dip of it's beak makes that sound. Others will chat as they hover or get close to your face. I'm jealous you have so many at one time. Here we normally see a max of 3 to 4 at a time.
As far as body sizes, colors, etc....yes we notice that too. Many are slender, others seem chubby. Some have shorter bills, others very long. Only the males have the Ruby throat feathers, We had a young male that had 1(one) ruby feather. He apparently wasn't old enough to have gotten all his adult plumage in yet. Some are more brilliant hues of green than others. Older females seem darker in color.
Have you ever seen any injured due to fighting?
We had a female 2 years ago that took a beak to her chest during a fight with another female. She had blood running down her chest. I stayed out to dark watching for her to come back. She finally did & was back again the next morning. Long story short she was very chatty, very friendly & our our last hummer to leave that year. She'd sit on a nearby hanging plant & chatter to us all the time.
We had another female that had some sort of growth hanging from her abdomen. It look like a dried up squiggly worm about 1.5-2 inches long. She came & went all summer & what ever it was never fell off.
Love your pics. Thanks for posting them.