Suggestions for vanilla add-on app on this forum.
place a check on the $PluginInfo['Name'] = array( and make sure the zip extraction directory matches the name, or make it so the plugin can't be enabled if the name is not the correct case (preferable), or make the disable function so it functions the same way as the enable when case is incorrect, so the plugin can be disabled from the dashboard.
add an up or down count option to the add-on for each plugin for votes whether plugin works as advertised or whether people like it or use it.
require the use of screen shots and a good description of how to use before it is even allowed to be posted.
purge plugins that don't follow the above rules.
user community make some useful comments to others whether you find the plugin helpful and it works or if you use on your site (might provide incentive to developers). Too often, there is no appreciation of a plugin that may be used and too little panning of plugins that don't work.
attempt to categorize plugin via function (e.g. category manipulation, discussion page manipulation, connection related, image related, etc.
BTW - what are your favorite plugins - it is obvious for some because of the thousands of downloads for a specific plugin, what about the little-known ones that haven't been downloaded as much.
What other plugins would you like to see?
I may not provide the completed solution you might desire, but I do try to provide honest suggestions to help you solve your issue.