Developer Unity Plugin for internal use.

Hi to all (sorry for my english), i need to develop a plugin for internal use. If u see the image attached u can see a Sprite (outside) canvas where we place a map, on these map we place multiple city (button with internal canvas), we really need these: in the editor unity: the possibility to create path from the city (these path need to be virtual not showed in the game when it play), the path need to be created in these mode: one empty gameobject that have inside all nodes. every node can be placed and removed on map using key combination, after the nodes i want to link one to other, so in the script inspector of the single node i want the possibilità to specify the number of nodes and the nodes. at the end i want put a sprite on these map and let them follow the path giving 1) start point 2) end point 3) velocity the script need to move the sprite over the point and link not and only using it. the moviment is on 2d map so the z can be locked. when the update is in action we want to change the end point to one of other sprite via code changin the variable in the AI script on the sprite. we think have in the same moment 70-80 sprited animated every time. se the code need to be optimized. we are open to suggestion or more implementation of these plugin.