As many said before what has been confusing at first is the way Bunpro works and should be used. How ghosts are introduced/exorcised, when reviews are available (this strange unlocking every half an hour…), how many reviews are left (negative number of reviews!?) are among the most confusing features IMHO.
Since I had a few years of (slowly) studying Japanese I started by learning N3 grammar points and not having a proper comparison of the nuances between similar points confused me a lot. One may say this is acquired by exposure, but I am of the kind that likes/requires plain explanation, and sudying similar grammar points in a row may be of help for me (bad memory => need to have the same things side by side).
As an SRS it forces me to review grammar points frequently which is what I needed as a not very consistent worker. Also the explanation are very concentrated and up to the (grammar) point which helps get the gist. For more detailed explanation the resources is also a great feature I use for difficult grammar points (but the several levels of details in explanation you guys are implementing currently seems very promising ).
And also the very friendly community is a plus. While the community is not very large (which I like) it is still very active and people have various interests, hobbies and experience with Japanese.