While I see your point about appreciating the unique strengths of both mechanical and hydraulic brakes, I can't help but worry that this "variety is the spice of life" approach might not be practical for everyone. Sure, for those who have the time, money, and resources to maintain both types of brakes, it could be an interesting experiment. But for the average cyclist, it might be more hassle than it's worth.
Let's not forget that hydraulic brakes, despite their superior modulation and reduced hand effort, can also be quite pricey and temperamental. As you mentioned, they require less maintenance than mechanical brakes, but when they do act up, it can be a real headache to diagnose and fix the issue. Plus, the initial cost of hydraulic brakes can be a barrier for many cyclists who are just starting out or are on a tight budget.
Meanwhile, mechanical brakes might not offer the same level of performance as hydraulic brakes, but they are generally more affordable, easier to maintain, and more accessible to the average cyclist. Yes, they might require more hands-on adjustments, but as you pointed out, this can also foster a deeper bond with your bike.
So, while I agree that each type of brake has its own unique strengths, I also think it's important to consider the practical implications of using both types of brakes. For many cyclists, sticking to one type of brake might be the more sensible and cost-effective choice.