If that's what you want, buy some paper and a pencil, because a computer-based notepad is not going to give you any significant advantage over the old-school solution.

I know this for certain, because the good old Newton allowed you to enter notes in "digital ink", and I tried this. Trust me, it is not good. You'll end up squinting at a low-res version of your own handwriting, on a petite screen where you have to scroll every five seconds. You can't insert text easily on the fly, corrections are a b*tch, repositioning text is nigh-on impossible. At least Newton ink had one advantage: A cursor. If enabled, ink text could be scribbled everywhere on the screen, but would be inserted at the current cursor position. I'm not sure if Xournal can do that, but if not, you're going to squint even more, trying to get the ink where you want it to go.

Luckily, Newtons recognize my handwriting almost as quickly as I scribble it down; I can write big or small, the text is allways converted into the same easily readable font; I can correct or insert text using simple, intuitive gestures and copy-paste is a straightforward select-and-drag.

And best of all, I end up with notes that I can still decypher six months later.