Writing a GUI without a designer is a PITA. So I elaborate a bit on the Visual Perl .NET part. I have successfully created two projects that use this product. It's quit nice. You can use the whole .NET class library from "perl scripts" (.NET exe binarys), but the syntax does not look very perlish. And you can write .NET components that can be used from other .NET languages.

That makes using GUI and Perla piece of cake. You click your GUI together and put the logic in the Perl .dll's. The power of the .NET library and CPAN in one program.