I don't think Haiku, inc would want to fund porting of non-native apps, indeed. And as shown in the screenshots, it already runs anyway
Being myself a vim user, I don't feel the need for an IDE. I also discussed this with some other devs, and they did not like the idea of "integrated" in IDE much. When you think about it, it goes somewhat against what I mentionned above: the strength of Haiku is the ability to combine small apps, GUI or CLI, and build your own workflow.
An application that goes a little in this direction in the application development area is Paladin. It is just a project manager, and relies on an external editor to edit the files, and on a makefile to build them. There is more work to do, for example we should get DontWorry / BeHappy working on Haiku again for easy access to the API documentation (Qt-Assistant like). We should also investigate porting YouCompleteMe or some other similar engine that would provide intelligent code completion in text editors - maybe as a generic input method. And, we should work on that "session" thing to allow you to save all the windows of your project, from these 3 or 4 different apps, in a single project file that you can easily reopen later. And let's add the Aukland Layout Editor for GUI design, maybe.
Well, at least this is my vision of things, and QtCreator does not fit in very well, being a monolithic app. You can see they are aware of the problem, as for example they have a "vim" mode in their editor (which didn't come anywhere close to the real thing last time I tried it - but that was a few years ago).
Building a workflow with small applications means it is easy to replace or update just one of them at a time, allowing for more competition. When there is one big app doing everything, suddenly, all competitors must re-implement all of its features, and cannot replace just one small part of it, even if they do it 100 times better.