Thank you for your advice and review!
Thanks to them, I’ve updated the node header colors to "converter" like math nodes!
This will be released in the next update (note: the controller remains red in Blender ≤ 5.0).
Regarding the deletion of arbitrary middle rows, I'm sorry, it’s a bit complex to implement right now and will take more time.
I am planning a future update to increase the flexibility of formula management, including these improvements.
For now, please handle this by moving your formulas up and deleting the empty slots at the bottom. Thank you for your patience.
This addon really helps a lot. Just a little advice. Can you make the internal group color tag be converter by default so that the math controller node will also show converter color tag? And is this possible to delete a arbitrary line instead of the last one(For example, i have f1,f2,f3,f4 and f5 now, but I want to delete f2 and f3)