It's a shame that Reddit relies so heavily on their "default" front page experience.
99.9% of people looking at Reddit will never see how good and useful it can be. My front page is just the stuff I'm into - a couple dozen niche subreddits with good cultures. It is nice. It is my favorite place on the internet.
Most people will never take the time to make an account and curate their subreddit subscriptions.
Could that process be improved and streamlined? Absolutely yes. When you make an account -- or perhaps even before -- it should probably hold your hand and walk you through a preferences discovery process.
As it stands now, customizing Reddit is effectively a collection of "power user" features and we all know how that goes: only a tiny fraction of users will ever bother.