If you want to get a firm grip on the personality based conflicts among your characters to use for texture, jokes and escalations, consult an astrological compatibility page.
There is so much character development already done for you there, and it’s all boiled down to conflicts you can transfer directly to the page.
Seriously, making your characters textbook astrological signs is excellent practice in showing them on the page as distinct individuals.
Your Virgo/Taurus friendship is going to look a lot different than your Gemini/Libra one, for instance.
It sounds like a cheat, but it’s a legitimate way to sharpen your characters and their relationships without reinventing the wheel.