Earlier quoted context omitted.
The replies you'll get are "you make your own reddit, just remove the popular subreddits!" but you're right. reddit is usable for hardcore users that want to invest real time into their experience, it's atrocious for casual users (that don't care for the meme spam). There is a large hole that (new) Digg could fill.
I'm not sure that 'hardcore' is the right requirement for Reddit usability. It takes all of 5 minutes for a new user to register an account, then customize their subreddit subscriptions. That said, it's the default front page that provides new users with their first Reddit experience, and sets the tone for their overall impression of the site, and when they've got r/pics, r/WTF, r/politics, and r/atheism on the defau…
Nudging the participants in some of the big communities into better commenting behaviour seems achievable (less users go vote in comment threads, most communities manage being self-policing), but driving out the meme generators isn't achievable from votes only. They are what the lowest-common denominator of the user base wants to see, and what they upvote.
On the other hand some of the smaller communities would benefit from more recruitment, particularly of dedicated users, but that doesn't have to come from the frontpage. Tapping into other social networks, via things like twitter sharing and per-subreddit twitter accounts (like StackExchange does), would be a good avenue for that.