I'm currently playing around with the plugin interceptors. Currently the only way to handle the order of plugins is by the sortOrder attribute. Unfortunately that's very lmiited as it only accepts a hardcoded integer value. Especially if you have dependencies between different modules it's very risky to use these, as if some other module changes it's sort order your extension might break.
Would Magento be interested in a solution where you could define a before or after attribute (similar to the layout blocks) to define if a plugin should be run before or after any other specific plugin? For me that would be a great solution to also handle bigger dependency chains and it's less likely to break if when the amount of plugins is growing. What drawbacks can you see in this solution?