I don't like it that most of the otherwise awesome programming languages had to be purposefully handicapped in terms of syntax and syntax-related features simply because they have to appeal to the mythical "Average Joe Coder" that dismisses things simply because they are "weird" or "can't keep track of them in his mind" (when the whole point of those features is to "outsource" certain things away from your mind and into the tools/language, and "cheat" by "stealing" some extra manifest-IQ points in the process and be able to write code "above you mind's limit").
There's tons of wasted effort writing "code intelligence" and "static analysis" and other related tools for languages with hostyle syntax. And tons of auto-refactor, auto-code-rewriting etc. tools that could exist and make work with legacy apps 1000x easier, if the languages we use would not have "features" to make the actual writing of such auto-coding tools prohibitively expensive...