Let me just chime in, it's just my experience and opinion.
I have been living in Japan for over 5 years, but never really did long periods of proper study, my knowledge is all over the place. I can hold daily conversations and read signs and simple texts, but not newspapers, nor long lectures or entire movies.
I did RTK1, then stopped and forgot loads.
I am doing RTK1 again, but this time I look up every kanji, and check which reading and consequently which word is most useful to learn. I then replace the English keyword with the Japanese word, which ideally consists of multiple kanji. I change the kanji learning order, depending on what other kanji are in those words I look up, and also on the readings.
The more connections you can make to remember something, the better.
I connect kanji, words, and readings. I can do this now because I already know a bunch of words, and can at least vaguely remember over half the kanji.
Take the word 冷凍庫
I was confusing the first 2 kanji, couldn't remember which one was which. I already knew the word 冷凍庫 though, I mean, I would understand it if I heard or read it..
I then realised that 冷 shares れい with 令, and 凍 shared とう with 東.
After realising this, the word, the 2 kanji, AND the readings have been easy for me. They were all connected. Now I kept discovering that this applies to many kanji, and it helped me greatly.
I told some of my Japanese friends, and they told by looking at the primitives even they often simply guess the readings of difficult kanji. They also mentioned they learned many kanji by the words they are in.
Indeed, many kanji have several readings, but most of them have only one or two main readings, which if learned, can be very beneficial. I don't think you should focus on mastering kanji completely, but rather try to get the part that is most useful.
So don't obsess about what you are NOT learning, instead focus on what you ARE learning.
Look up the kanji, and look at the words, which examples are most representative? I usually think about the kanji in a what can be articulated to: "This kanji tends to describe an X aspect/feeling/characteristic of the words it's in".
Which examples make use of the primitive reading? Sometimes, even if the primitive reading of that particular kanji is rare, it can reinforce remembering the readings of other kanji with that primitive.
Then make a decision on which word(s) to pick, and don't worry too much about the words and readings you leave out. Those other readings or words can come later as you pick them up while reading/listening.
Perhaps most importantly, all this makes the kanji, and the language, more interesting to me.
So in short:
"I'm debating about whether or not I should actually take that route or if it would just be better to start vocabulary after something like RTK."
Take that route by learning vocabulary, keep an eye on the primitives and readings, base the order on connections, and use as many connections as possible, but focus mainly on the most important readings and words.
RTK2 is actually quite a useful reference for this, but I understand that he probably wrote it after learning it all. Will all this be as easy for someone who doesn't have any vocabulary knowledge. Likely not, but you can try.
Please see these points as observations, not from someone knows better and and succeeded, but from someone who failed over and over, and do with it what you like.