Cool thing, quite low amount of steps! Also was the Aceton at Room Temperature? I think there is no reason why you cant also go to boiling @ 56 °C.
Also cool picture with the crystals ... I think just even getting ANY crystals is a high chance of having the desired product. Upon salting there is no other Alkaloid which should precipitate as "-Benzoate other than Bufotenin.
Holy crap thats a lot! When I did that old 2020 TEK it was always just 1-3 %.
So as you said, maybe there is the risk of partial Bufotenin-Bufotenate equilibrium, thus loosing some goodies at the end. But even on top the old TEK uses soooo many steps, that this is just alone a big reason for yield reduction.
I would not be too distracted by an off-colouration. Bufotenin on its own has an increased electron count, so naturally absorbs more extended towards the visible spectrum. Same with Harmalas, which then have a tan colour. Even my most-rex'ed Bufotenin always had a slight tan colour. So naturally for the "-Benzoate it might be the same. So getting it not totally white might not mean anything, but of course washing it would be anyways desired.
Actually I found it astonishing that Bufo-Benzoate even precipitates from Aceton. I would expect there is still SOOOOOOOME solubility here. So when going with boiling Aceton on the Benzoate, maybe just be very cautious by putting that boiling Aceton later on in the freezer and check if you get any Bufo-Benzoate back. Could be also reducing your juicy 4,8 %, even though a little bit of that may be contamination, but surely not too much.
Some things that would be now very interesting:
1. Solubility of Bufo-Benzoate in Aceton. You could measure 100 mg of your multiple grams AFTER cleaning and then boil in increasing amounts of Aceton until dissolved. Then after noting that volume also check how much precipitates in the Freezer.
Then it would be interesting if solubility in Aceton might be still "too high" and you could get even more after the salting step. Then Ethyl Acetate might be the candidate.
2. Before pulling, separating your seed/base powder into 50% 50% and do the comparable extraction with Aceton and EA on the respective parts. Then compare the outcome. I could imagine EA works better here, sadly its just a little less accessible.
Reason might be: EA might dissolve Bufo a little less well, but you can boil it even 20+ °C more. Given the assumption heat does not make any problems here, this will increase solubility even higher than Aceton at 56 °C. Then later when salting and putting to the Freezer, EA will definetly have an even lower solubility for Bufo-Benzoate.
So in total EA could make for a higher yield. But your 4,8 % is already super high, so Aceton might be still efficient enough.
Now last question of course is simply if that is indeed (nearly) pure Bufo Benzoate. Considering that there was no other workup step, it means the precipitation comes directly from a wild mixture of plant-derived molecules. Considering that you got ANY crystallization is a strong sign that we truly have Bufo-Benzoate.
But reason why it anyways would be very interesting to know, is that if that truly is Bufo-Benzoate from a high purity, then the old 2020 TEK here is quite obsolete, except if you truly want the Freebase (and I would not know any reason why this would be the case).
So if that stuff you got is already pretty pure, then this is a much better 2023 Bufotenin Extraction 
EDIT: So just to make a very easy purity determination, do you have TLC Equipment and could make a photo?
It should look like:
TOP Eluent
Benzoic Acid
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Bufotenin
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START
In Methanol + 1 % NH3
No spot should be inbetween and definetly no spot remaining at the START.
