zendorf not all of my apps are Construct 2 apps, but I do have some that are Construct 2 + mopub + cocoonjs with ads (the more non-child directed apps).
CocoonJS works ok with ads, but it doesn't seem to work as fast and smoothly (especially full-screen ads, these seem to have trouble loading sometimes) as it does as it does developing with native or other game engines like Corona SDK .
Crosswalk has potential but the deal breakers for me are still it's performance (not as good as CocoonJS) and lack of support for IAP and ads (which like you say should come eventually).