I think adding delphi support will really matter here. I have both Delphi and FPC/Lazarus installed, but I'm more familiar with delphi so I use it for my projects. I think there are quite some others who use only Delphi.

The other features are also quite nice.

However, if you really want more people to use it, you should show it off a bit more. I knew about Allergo for some time, but I was never interested because I was writing my own engine/library. If you let us know about its features + some screenshots, more people will actually check it out.