One thing I love about playing guitar is - no matter how good I get, there is always room for improvement. It's a never ending journey and I enjoy every step. I admire your desire to continue improving your skills.
I am not sure what your personal definition of "advanced" is - but it is clear that you want to become a better guitar player. It is also apparent that you are willing to put in the time and effort to accomplish your goal of becoming an advanced player.
There are many paths to improvement. All of the options you mentioned in your question and all of the options presented in the answers thus far, will help you improve. You did not mention lessons which can help tremendously if you have the right teacher, but I will assume that self study is your preference.
Everyone's path to improvement is different. One method may work better for some, other methods may work better for others. The common goal of study, exercises, drills, and practice - is to improve your skill at playing your instrument.
I don't want to discount the importance of practicing scales and learning theory and new techniques - but I would like to explain the method I prefer to utilize to continually improve my playing ability.
First let's look at why one would want to even learn to play an instrument. I learned to play the guitar because I wanted to be able to accompany my singing and perform without an external accompaniment source. When I started writing songs, my ability to play the guitar took on an even higher purpose - that of helping me to compose the music to go with the lyrics I write. Other's learn because they want to perform for friends, play in a band, jam with other musicians, or perhaps simply for their own enjoyment.
In short - you learn to play an instrument (such as guitar) in order to be able to make or play music. And making music involves more than just playing scales and playing notes and chords. Nobody learns to play an instrument just so they can play scales. They want to be able to apply the skills and theory to the art of making or performing music.
More than anything else, I play guitar because I enjoy it. I spend some time practicing scales so I can improve. But for me personally, the more enjoyable way to improve my skills and master new techniques, is to continually learn to play new, more challenging songs, or play more challenging and more advanced arrangements of songs I already play.
I almost always have 4 or 5 songs I am working on and I like to spend most of my practice time working on mastering those new songs. The songs or arrangements I work on will incorporate the skills I want to improve, whether it's picking hand accuracy, picking hand speed, fretting hand techniques, new chords, fast chord changes or whatever.
By learning to improve my skills by applying them to more complex arrangements of actual songs, I feel that I am learning by making music - which is why we play an instrument in the first place. There is more to making music than being able to faithfully execute scales and techniques. Making music involves, timing, rhythm, soul, feeling, touch and all the nuances that make our playing musical. So when I focus on learning new songs to improve my playing ability, I am also learning to make my playing more musical!
Also, I find it far more enjoyable to learn a new song than to play scales and practice drills. It gives me a measurable goal. And I get a greater sense of accomplishment from mastering a new song that I previously could not play - than I do from getting faster and/or more accurate playing a scale. I am working towards "look - now I can play this new song" instead of "look how fast I can now play the A minor pentatonic scale".
I play guitar for the joy of being able to play music (which to me means playing songs). If I improve my skills by learning new songs, I have more fun and expand my musical repertoire at the same time as improving my playing ability.
Rote repetition has it's place, but it also has its limitations. Unless it gives you pleasure to play scales backwards and forwards - I would recommend that you challenge yourself to learn some new songs or new solos that you can play as part of the process of making music and make that a big part of what you do to improve your skill.
Then you will not only become a better guitarist, you will become a better musician. And you will derive more enjoyment from the time you spend with your instrument.
Good luck on your journey.