I have an idea for campaign in my head but I need to find a good system to run it. Main thing I want is a system that would allow people to play humans, humanoids, and non-humans, with enough system and character customization depth to make the differences feel interesting and meaningful. Basically, if a player wants to be a fire magic-wielding phoenix or a psychic cat, they should be able to do that.
Ideally the system would also have at least some level of support for typical fantasy adventuring stuff (dungeon crawling, combat, social intrigue, etc.)
Target limbs in combat at a penalty to hit, if you do at least a certain percentage of damage the limb is destroyed. Each missing limb gives penalties to movement and any physical actions. The more limbs a bug has, the easier they are to destroy, but the penalty per missing leg is reduced (IE with 4 legs you lose 1/4 movement and -1 to all actions per leg lost, with 8 legs you lose 1/8 movement per leg lost and -1 to all actions per two legs lost.
For replacements, they can get bug cybernetics that give bonuses. If you have more legs, you need to replace more of them to get the same effect, so it's a balance of fewer limbs for a cheaper bonus vs more limbs for more consistency.