So I'm still thinking how I want to replace this blog. I still plan to write something from scratch, for fun's sake.
One thing I'm sure of is that I don't want to write HTML by hand, at all, under any circumstances. HTML and XML are not human-writable or human-readable languages. They rely too much on things human beings suck at, namely consistency and repetition. Forget a closing tag? Typo a tag name? Now your document is malformed. Undefined behavior, at best. It's too verbose, it has too much needless punctuation.
It's also too hard to manipulate it or do anything with it after you write it. There's XPath, which is itself a mess to work with, manipulating huge strings of crap via slightly smaller strings with its own funky syntax quirks. I've never found an XML-parsing library with an interface that I liked, and I've had to use them extensively in Perl, Ruby and Python.
Second thing, I plan to use my programming language to write the HTML for the skeleton of my site for me. Opening, closing, and properly nesting tags is something a machine should do for me. Making sure my tags belong to a well-defined list of allowed valid HTML tags is something a machine should check for me.
More than likely I'm going to write this in Clojure, because s-expressions (and better yet, a combination of Clojure literal lists, maps and arrays) makes writing HTML very easy and foolproof. I've also written an HTML-producing DSL in Ruby in the past though; it's not hard to do in any language.
Another thing I'm sure of is that I need a good anti-spam system but that I have no idea what that system should be. Askimet in Wordpress has caught 50,000(!) spam comments since I started my blog. Some spam still sneaks through on me now and then. I've never used a CAPTCHA and don't plan to; they just don't work. I'm probably going to come up with some funky custom anti-spam measures (which are invisible to users) and rely on the fact that no one is going to take the time to break it. My site isn't a huge or popular target, so here's hoping.
A third complication I'm dreading is how to do this without breaking every link anyone ever made to my site. Wordpress's permalink system is OK, but I'd like to change it. Problem is I can't change it; every link to my site from another site is a dependency. So I might have to mod_rewrite redirect the old URLs to new ones, or use two permalink schemes simultaneously. I don't know.
Fun times ahead. How to design a blog is a problem lots of people have solved but no one has really solved perfectly, or else there wouldn't be so many frameworks and packages to do it. The good thing about writing your own from scratch is that it'll work exactly how you want. Wordpress is close but not close enough.