Ideas for better corroding resistant probe

[BenRoe]

Since coating the probe to make it corroding resistant, seems not that easy and is also an extra assembly step.
I wanna share my ideas and invite everyone to join.

1. My first idea is to move the copper away from the edges like flower by diyruz.
   
   Does someone know if the frp4 PCB material soaks watter?
   If yes this idea should not improve the corroding problem.

2. The second idea is to create two parts design with a interchangeable probe.
   The manufacturing coat for the probe should be under a 1€.