The main difference is the degree of separation. A plant protein isolate generally contains a higher proportion of protein and smaller amounts of starch, fibre and fat. A concentrate normally retains more of the other components naturally present in the original plant.
Neither form is automatically better. The right choice depends on the actual nutritional values, ingredient list, flavour, texture and intended use.
The two almond ingredients perform different functions. Almond protein increases the protein content and thickens the mixture. Almond butter adds roasted flavour, fat and a smoother mouthfeel.