For what is worth, it would like to offer my $.01.
What made Construct an appealing choice was not only that it was good but also that it was free. This was also the main reason why I succeeded in adopting it for the class I was teaching. If it adopts a license scheme $$/seat (even if just $25 like Game maker), I'm pretty sure I'll have to switch to something else for my course (most likely GM Lite).
In a world where people can now use engines like Unity and Unreal basically for free also for small commercial projects, I'm really afraid an old fashioned license model will be unsuccessful.
My suggestion for the Construct developers (who obviously need to get some money out of their huge commitment) is to try get development funds (Kickstarter, IndieFund?) first. I guess $10-15k should be a relatively easy target to achieve (recently the people behind a new game history museum in San Francisco, the MADE, made more than $20k through kickstarter) and then make money by giving online classes, writing books, offering paid support as consultants etc. while maintaining Construct free.
In this way I believe the community will still grow and Construct will become more and more relevant which I'm afraid it won't happen if a license fee is applied.
In any case, to all the guys working on Construct: take care, you rock!