My issue with getting better at vim is that I've gotten to the point where I'm comfortable moving around text, copying/pasting, and everything I would normally do with a mouse. I know vim is so much more than that, but it's one of those things where "you don't know what you don't know" and because of that, I don't have the incentive to continue learning. Hopefully this post will inspire me to incrementally advance my…
For example - '%' matches parentheses and braces. So if you want to delete a block of code, you could go to the opening (or closing) brace, and do "d%". If you wanted to indent only that block of code, you'd do "=%". In this context, ":help motion.txt" makes for a good read.
Apart from this, I'd also recommend listing down things about your current workflow that you find irritating, and trying to find solutions for them in vim.
For instance - I wanted to be able to browse through cscope matches in a regular vim buffer than the ridiculous less-like interface that's the default. I found quickfix, which solved my problem neatly. I then wanted to open each match in a vertical split, rather than in the same window - I ended up writing a little bit of vimscript and a keybinding for this.
Sometimes, when going through a gazillion cscope matches, I find it convenient to hide stuff that isn't relevant - I use (manual) folds for this purpose.