Replying to your other questions:
Its been a while since I played chess regularly (in a chess club), but:
Two bishops (of different colour) is actually not that difficult. There are some simple heuristics to help you there (an LLM might actually tell you these, haven’t asked;-0)
Bishop+Knight is, in my opinion slightly more complicated, there are some ‘tricks’ necessary to keep the king from running from one courner to the next.
Bishop+bishop is - in most situations - a draw (you need three knights to mate).
Two bishops (of different colour) is actually not that difficult. There are some simple heuristics to help you there (an LLM might actually tell you these, haven’t asked;-0)
Bishop+Knight is, in my opinion slightly more complicated, there are some ‘tricks’ necessary to keep the king from running from one courner to the next.
Bishop+bishop is - in most situations - a draw (you need three knights to mate).