I use flax meal in my recipe and yeah it doesn’t dissolve well but I got used to it fairly quickly, it doesn’t bother me at all I actually kind of like it. I use it for the fiber and Omega 3 and I haven’t looked too hard for a replacement since I got to liking it but a combination of fish oil and another more finely ground fiber could replace it.
As far as using peanut butter or ground almonds goes I’ve seen quite a few folks mention that they used almond meal in their recipes with good results (maybe they will speak up and provide more detail) but I haven’t tried that yet myself. What I do use is peanut flour and I really like it. I have come across a few places that sell it (couldn’t find it locally anywhere) what I have been using is this:
(I’m not sure how it works but I have a referral code BJG146 that is supposed to give new customers to this site a $5 or $10 discount for their first order if you want to use it. full disclosure- I think I’m supposed to get some sort of credit if someone uses it, but I’ve never had someone try it so I’m not sure if I really do )
Anyway, I like to use the peanut flour in my recipe, it doesn’t give a very strong flavor but you can definitely taste it. Depends how much you use of course,I use anywhere from 30-50 grams per daily mix. It’s really nice if you also use cocoa powder you get a chocolate peanut butter taste, just don’t use too much cocoa powder or all you taste is chocolate. It is also good for adding protein since it has a 2:4:1 ratio of carbs:protein:fat (if you use 30g you get 8g carbs, 16g protein, and 4g fat).
Luckily I’ve never had any type of nut allergies but I think it seems that we don’t see a lot of recipes with nut ingredients because like the “official Soylent” the most popular recipes try to stay away from anything that is a common allergen.
good luck with your DIY