Fictional Planetary System Stability

Hello,

I am developing a solar system for a story, and was wondering if there is any way to tell whether or not it is stable enough to not fall apart immediately. I would use Universe Sandbox, but I don’t have any computers that can meet the recommended requirements for running it. I have calculated the gravitational attraction between the planets and their star and compared them to those for our solar system to find any trends. I have also looked at Artefexian’s videos, but I know they use simplified math and don’t really touch on solar system stability that much. I know that stability of a solar system is a tricky subject and I’m mostly looking for plausibility.