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Ooh i swear i saw a similar type map in a warband mod but my opinion is absolutely amazing but for a full on castle does look more like a castle that would defend a small region or villgage but in practical use that uphill is absolutely gonna destroy attackers
Edit: Oh wait, I see what you're saying @NurAbSal ... If the forces need to retreat to the main structure they can be pelted with arrows... Yeah, raised crenelated walls on the sides of the bridge would probably be best.
To make it more realistic the big bridge should be atleast 1/3 less wide, also a draw brigde should be added, also a real life thing they did, that would reduce its artistical look is a "snake" or zigzag bridge that made it harder for a besieging army to bring in siege equipment and made them have to expose their flanks to archers when doing so. heres a link to a screenshot of what i mean in smaller scale: https://gyazo.com/5e0d8791eda3e5f69c8ba25c5bda151a