I think most issues ranted here are non issues. You have a pretty basic editor, with a basic toolset, and a basic setup of behaviors and plugins. Where Construct shines is that they have the Event sheet and the capability to make and add your own plugins.
Nothing for serious developers? Out of the box no, but if you're really that serious and in need of monetization the only thing stopping you is your own ability to create the plugin to fit your needs. Blaming the devs for not providing this and that plugin is a bit childish.
Ludei, Photon cloud, etc. etc. are providing their own plugins for C2. If there's any plugin you're missing go hunt down the service provider and ask them to provide one, or... get some skillz or invest in a coder, get the SDK's and make your own plugins exactly the way you want them.
I wouldn't call anyone "serious" who can't even invest in their own business, blaming everyone else for not providing a smörgosbord of everything that you "might need".
I have no need for monetization plugins, I wouldn't wanna ruin my game by slapping ads on it, so for me those kind of plugins is not something I would like them to spend their time on. But if you need it, check with the ad network to provide their own, make a case, we are so and so many who would like to use ur network, maybe they will do it. Or pay a coder to do it for you. If ADs is part of your business model and would allow you to earn money, why not invest in your own business instead of complaining? A decent coder should have you plugins done in a fairly short time provided the SDK's.