Tilly isn't as talkative in this episode as she is in the rest of the series; this is because the Houghton brothers originally envisioned Remy as the deuteragonist (hence here Remy's given more dialogue than her), before that role was given to Tilly and they realized Cricket and Tilly's relationship was more important.
Originally, the episode's premise was about Cricket trying to get everyone to remember his name, which is a reason why he wanted to impress everyone by launching a chicken into space. The final version is more about Cricket and Bill, which is better for the show's general theme of family values. The only remnant of the original premise was Cricket shouting "My name's Cricket! I'm your new neighbor!" after the chicken scares Gloria and the Big Coffee customers.
According to Chris Houghton, "Space Chicken" was the hardest episode to produce.
Despite being the first episode aired, it is technically the second chronologically after "Welcome Home", due to being developed as a pilot which often creates a lack of continuity. This was fixed on Disney+ when it's listed as the second segment of the first episode with "Welcome Home", which also includes all Season 1 episodes in the correct chronological order the Houghton brothers imagined.
According to the Houghton Brothers, "Space Chicken" was produced between 2014-2015 as a pilot, back when the show was originally called Country Club.