Hello there, I have to say that topic resonates with me a lot! Sorry in advance for my bad English and too many thoughts (long text). :D
It's really nice that there is nothing negative and everyone is trying to bring something interesting that could help the engine, that's one of the things I appreciate about Construct as a whole, the community, so it would definitely be nice to put more emphasis on it, see the mentions about the unofficial discord, it's really helpful and you feel good there, which for complete newcomers is essential information that none of them know.
Then I would focus on the first impression, which is essential for new potential customers, yes as already said it looks like a product for "children", whether by the presentation on the web or even a little for me unnecessary detour to add "3D" features because I myself do not consider it enough capable to create anything full-fledged and therefore I stick to 2D only and personally I have no problem with it to make only 2D games and Construct should not be ashamed of being only a "2.5D" engine because it is damn good at it.
Overall at the first glance it looks like an engine only for some simple games and not for serious projects like "here I'll play around and then I'll learn a proper engine", that's very sad, because we all know how powerful and great it is.
Now let me make a small side-step to my "life" with Construct. I started back in the days of Construct Classic and I really like using Construct to this day (C3), overall it suited me very well and I like how efficient it is, what I think about I am able to process very quickly and express my ideas, I think that is really unique for Construct. For that I thank the whole team very much for how far they have come since the beginning and I hope they will continue to do so, because I want to use ideally till my death. :D
So then it makes me even more sad when someone asks me "in what engine you did it?" and I say Construct 3 and nobody knows it, or like now a bunch of news and articles about the Unity controversy and what the alternatives are and nobody talks about C3, which is a big shame. People just don't know how good and efficient it is, and unfortunately even a first look at the web doesn't give them much of a feeling of a serious high performance engine, which C3 undoubtedly is.
Regarding the presentation, as it was already said here, that "we are better than X or Y" and "that we are 2x faster etc"... doesn't seem to impress people much, emotions through the stories/successes of the games have a greater impact. Yes, the blog series about developers (by Laura) was mentioned here, which is nice, but it will not reach new potential customers. I will read it as a long-time user because I know about it.
For example, I personally have worked my way up from small experiments and really bad "things" and XX unfinished projects to a hobby solo dev full-fledged release of the game on Steam as you can take a look here:
https://store.steampowered.com/app/1970010/Light_Bringer
Now I don't want to praise/promo my game, the point is that I proved it to myself and got to a higher level. I became GAMEDEV and it has been very exciting journey with Construct and for me it is something like personal achievement. You know I became more serious developer who will release his own full-fledged game that looks not lame :) I attended few game conferences with it and many other interesting things. Yes, I wasn't successful with sales, because I had a bad promo, but it is another story and my problem. The engine served me more than well and thanks to that I've made it to this point and I'm still moving on, and for that, many thanks to whole Scirra!!
Sorry for endless post... :)