Construct Classic was and still is open source, so what's your problem?
The new HTML 5 Construct 2 system still has a free version.
It's for you to decide what software is the most appropriate for your needs, and even Gamemaker charge for their new HTML 5 system.
This road has been covered many times in numerous threads. I suggest you read through all the debates and make up your own mind that way.
If your vision so exceeds your ability, then look to something closer.