The issue, for most of us, is that learning just a few techniques gets boring and we eventually move along. Having a more extensive "vocabulary" to learn, along with deeper physical principles, has kept me training and improving. It's all useful stuff, but some is more complex, so I keep finding more layers I can work on. That consistent practice means I'm always as ready as I can be to defend myself, rather than having several years of rust to dig through.
For my part, I've started moving as much of the simple stuff as possible to early teaching. This way, if a student quits after a few weeks, they are probably better prepared to defend themselves.
I heard this from my Sanda Shifu and I heard this from one of my xingyiquan shifus..... "training is boring". Meaning if you want to do it right, it is long hours of repetition. But with that said, in my quest to not be bored, I have trained Jujutsu, TKD, Taijiquan (Yang, Chen, dabbled in Wu and Sun), Baguazhang, JKD, Xingyiquan, Changquan, Wing Chun, Karate, Sanda and probably one or two more I can't remember. I also had a job once that required me to get into multiple confrontations and I was on many occasions able to talk the other guy out of doing what he wanted to do but at times I had no choice but to act and most of the time, qinna handled the situation, but I will admit that multiple jump kick with a spinning kick I could do at the time looked much cooler, however I never used it once in any of those confrontations.
I also spent over 20 years of serious training of Yang style taijiquan only to realize that a long form, 2 fast forms, a staff form, 2 Jian forms, a Dao form, multiple push hand drills and a 2 person form was just way to complicated, and I came to this conclusion after I was given permission to teach Yang style and after a lucky encounter with a Dachengquan guy.
If I were a younger man I would likely focus on JKD for a few years because my short time in it taught me volumes about many of the other arts I trained, especially Xingyiquan. JKD is uncomplicated and rather direct and I like that. But for those same reasons I like Xingyiquan, it is uncomplicated and rather direct, but can be painfully boring to train (literally painful at times). But if you train it right it works well on many levels from SD to health. My current thinking is that Dachengquan simplifies things even more, but can be even more boring to train. But again, done correctly the reward for that training are immense.
What old age, injury, multiple arts, multiple confrontations and years in training MA have lead me to believe is that Flying Crane is absolutely correct. and again to quote Bruce Lee.... the goal should be "simply to simplify"