Just wanted to throw in my $.02 worth.
I've been studying martial arts/combatives for the majority of my life. I earned my black belt in Aikido, and have a good amount of experience in Judo and boxing. After being out of AIkido for a while, I went back to it about 2 years ago, and found that my priorities had changed since the last time I'd been studying it seriously. As such, I sought out something much more combatively oriented, and was lucky to become involved in Sayoc Kali, Atienza Kali, and the Warriors Way System of Guro Harley Elmore.
I can only speak from my own experience and observations, but arts like BJJ share some of the same shortcomings mentioned in regards to arts like Karate, Tae Kwon Do, boxing, etc. That is to say, BJJ is a sport. It is an art derived from another art (Kodokan Judo) that was developed as a hybrid sport/self defense art/physical education system. In traditional BJJ practice, as in Judo and many other arts, practice takes place primarily between 2 people. These arts may have forms or series of techniques that address the need to fight more than 1 person, but those are auxiliary to the main focus of the art.
The sportive aspects of Judo and BJJ are a sort of double edged sword: on the one hand, you are practicing executing techniques at full speed against an opponent who is resisting you fully, which in spirit is about as close to combat as a person can safely get; on the other hand, there are rules, and you're only fighting one person at a time. If you're main area of study is grappling based, and you're lucky enough to get into a fight with a lone person who has no friends or relatives in the immediate vicinity, then you'll probably be ok taking him down and choking him out. BJJ and Judo techniques are absolutely devastating. Unfortunately, though some may take the time to train mass attack scenarios into their BJJ and Judo practice, the average person who studies those arts is going to be poorly served if the person they are fighting isn't alone (which, in my experience, is more often than not). Putting the sleeper hold on someone is a great way to knock them out, but when their brother-in-law runs up and stomps on your neck while you're executing perfect ground game, you're boned. If the only answer you have to someone bringing violence against you is BJJ or Judo, and you've been lucky enough to win those altercations, then you've been extremely lucky. It's my opinion that those arts (and indeed, most arts), offer an incomplete or inadequate set of responses to physical conflict.
That doesn't mean that I think BJJ and Judo aren't wonderful, fulfilling areas of study, with huge benefits to offer practitioners. They absolutely are worth the time and effort it takes to become skilled in them. It's my opinion, though, that if a person is looking to study martial arts as a means to gain self defense skills, then cross training is essential. The BJJ may have been working in the past few altercations you've had, but things can go south quick when someone who knows what they're doing puts a stiff jab on your top lip. Study boxing, ground work, weapons, standing grapplig, etc. Hybrid systems are also a fantastic way to go about obtaining diverse training. The Inosanto and Warriors Way systems, for example, offer students training in Jun Fan Gung Fu (Bruce Lee's system - kick boxing, trapping, etc.), Filipino Kali (knives, sticks, swords, etc. as well as Panantukan (Boxing), Sikaran (Kicking), Dumog (grappling)), Indonesian Silat (a complete system encompassing weapons, empty hand, grapplig), and other systems. Hard to beat an art that will train you in most, if not all, of the areas you may need in physical combat.
I personally have chosen Sayoc Kali as my main pursuit. It is absolutely, hands down, the most complete and forward thinking combatives system I've ever experienced. I would encourage anyone interested to check it out, PM me for more info.
On the topic of mindset, I've always loved a quote I heard second hand that was attributed to Tuhon Tom Kier of Sayoc Kali. The essential idea was that, if you took two identical twins, just alike in every way, and sent one to study with the best martial arts teachers on the planet 10 hours a day, every day, for a year, and sent the other to a place where they were made to fight, 10 hours a day, every day, for a year, with no training whatsoever, and then had them fight each other after that year, then the one who had spent all of his time fighting would win easily. Training can only provide a facsimile of combat; one in which the student's safety is at least somewhat protected. It's for this reason that finding a system and/or teacher that deals with training for real combat practically, rather than as an auxiliary practice to their main art. Any art can be effective, if the person using it has been well trained, and has been pushed in that training to apply the techniques of that system against an aggressive and resistant opponent.
I personally believe that H2H training is as important, if not more so, than firearms training. I love shooting, I believe that firearms training is essential (and fun), and want to train in firearms with as many amazing instructors as I can afford, but I truly believe that most people would be better served devoting more time and money to fitness and H2H training than to firearms. I want to be fully capable in all forms of physical combat, no matter if I'm carrying a rifle, a shotgun, carrying concealed, only have a knife on me, or even if I'm in a non-permissive environment where I'm either fully unarmed, or only have everyday items such as pens, etc., at hand. It's intimidating knowing how much knowlege is out there that I haven't even scratched the surface of, but it's also pretty exciting, and it's worth the effort.