To be frank, my first impression of the copied text is "That's a LOT of buzzwords!" "Lifestyle design"? "... brain-intensive replacement for consumerism with an S-shaped learning curve."? "The Web of Goals can be seen as an evolving life-story that automatically minimizes waste (any kind of negative side-effect) and allows for the maximum possible number of opportunities in a rich world, or maximum resilience in a poor world."? It sounds like a MadLib from a marketing and self-help seminar.
Okay, that's my negative reaction to the presentation of the material.
Now, that being said, if one's plan is to retire early, that's fine. But are you taking pleasure in the journey to get there? If following the tenets of "simple living, minimalism, frugality, DIY ethics, survivalism, car-free living, and others" gives you pleasure, by all means, simplify, learn how to DIY, manage your life car-free, and so on. If it becomes an obligation to live by minimalism and frugality, that's not Epicurean. "Being forced to do something is bad but we are not forced to live with being forced to do something." (My translation of Vatican Saying 9) Epicureanism is about being prudent in your choices and rejections, judging what will or will not happen if your desires are fulfilled or not. The goal is a joyous life. Whether that life is minimal or not, is judged by one's reaction to that lifestyle and whether you can find pleasure in it.
I also don't think it's fair to Epicurus to say he retired early. He founded and served as head of a school. He wrote voluminously. He most likely taught, wrote letters to his friends in far-flung places. Plus he obviously took pleasure in these pursuits. I'm not clear where his money came from to purchase his house and The Garden, possibly an inheritance but also money from students, but he must have been prudent in his finances to be able to will the Garden to his students. Self-sufficiency is not the same as early retirement.
Personally, I think it is more important for me to find pleasure in what I am doing - as much as possible - than to follow some rigorous "brain-intensive" plan. That's not to say I wouldn't make prudent plans if I won the lottery and retired early, but even playing the lottery (infrequently!!) is pleasurable. It gives me a chance to consider "what if?" but I don't dwell on my inevitable loss. And I realize the lottery is not an ERE strategy, but it's probably as close as I'll get to retiring early.