What would make my life so much better and easier (and also get away from tools like lucid charts and Omnigraffle) is having custom objects. Even better is custom connection/anchor points where the line could connect. One step better is easily having good support for multiple connections to an object.
If the object can be created in Figma and then converted to items for Figjam would make amazing custom objects, way better than other tools.
Lucid allows connections all over the place, which can be messy, Omnigraffle allows placing custom anchors. Both have good and bad points, but with how well Figma could be used for precise placement of those anchors I think placing custom ones it better.
Really it comes down to Figma and Figjam being so close to replacing Sketch, Lucid Charts and Miro in a single tool, and I would be very happy if this is the direction Figma is going.