Many requests in the past are rejected because you don't have the time/sense to implement it or the design does not allow to do it.
I don't recall any moment in the past where a developer offered to help develop Hiawatha.
When you die this project will end and that would be a sad story.
Not really. Because not many people use it. Max 100.
A lot of companies won't use Hiawatha because it is a one man project...
Not true. Most companies won't use it because they use Windows, and therefor IIS. The companies who use Apache, use Apache because it's all they (= their IT staff) know.
In my opinion the Hiawatha Project should be exist with a team of core of developers with you as head developer...
Agree. You give me a team of core developers?
Believe me. I've done all I can to make Hiawatha more known. But most people won't move away from Apache, because they don't want to or they can't, because the ugly applications they run are made for Apache and Apache only. There are a LOT of crappy applications out there that follow the Apache-standard, not the official web standards. The world simply doesn't need another webserver.