The question is, does it really matter? I am talking from personal experience so perhaps my conclusions differ a lot from others' . I feel that a website's URL is only an entry point and not really not important in the long run.
I have noticed that people don't exchange URLs anymore in conversations (I remember that being the case when the Internet was younger). People will usually discuss a site and when asked for instructions will say "Search for this term on your favourite search engine". On social media and blogs that are maintained by computer scientists, the link itself doesn't really matter, since people will just click on it and need not memorize it. It is not uncommon for the URL to be hidden behind a descriptive name, especially in blogs. If there is a problem with length, let each user deal with the url shortener services (e.g. for twitter).
After people have discovered the site and if they are really interested, they will make sure that they can come back. Personally, I used a bookmark in the early days, but usually I just type "cst" on my browser address bar and let my surf history take care of the rest. It happened that at times I completely forgot the URL after deleting my history, I simply searched for "cstheory" or "cs stack exchange" on my favourite search engine and there I was.
Perhaps we would see a better ROI if we tried search engine optimization, of course by benevolent techniques. In a real world example, it's more important for a customer to know how to get to a store, rather than knowing its address. An obscure address name does not matter, if the store itself is easy to find.
This could also help see what search terms are related to this site, how easy is to find this site and other data that complement SE data. This data can prove very useful in deciding our further strategy, possible target audiences, how successful we have been and so on.