may be if I overload invoke operator I will get very close to what I want with parentheses?

You can overrider invoke operator. Syntax will be like:

"XML encoding with Kotlin"()

actually for simple case with title easier just to write simple version of title function to use it without lambda:

title("XML encoding with Kotlin")

This works only for simple cases, but also for most common ones. For cases where I have complicated dsl with mix of different operators I would prefer more explicit approach (for example

text("Some text")

instead of

+"Some Text"