Viability of some ideas?

Hi guys, 

I'm new to the rust plugin/modding scene and had some ideas I wanted to work on but I'm having a hard time finding out if this is even possible. As I understand there are some limitations to as adding custom items or reworking existing items.

The idea I had was for a more cohesive primitive/hardcore rust experience and stuff I am looking to get working are as follows:

  1. Make syringes not be consumed on use and give them a durability.
  2. Make custom crafting recipes (refilling syringe).
  3. Make crafting consume scrap prefarebly form the slot in the workbench(could be included in the recipe).
  4. changing workbench levels for crafting certain items.

these 4 are the ones I'm wondering the most about. There is allot more stuff but similar plugins exist already and I should be able to rework some existing ideas.

I'd love to hear what you guys think about these things after reading some forums and stuff I am afraid it might not be possible. 

Most of them can't be done properly:
Make syringes not be consumed on use and give them a durability.​

I am like 90% sure you can't add condition to normal items. Either it will be not visible

Make custom crafting recipes (refilling syringe).

In custom UI its possible. In client one - not really

Make crafting consume scrap prefarebly form the slot in the workbench(could be included in the recipe).

You can't add extra slots in workbench UI

changing workbench levels for crafting certain items.

That's what you in theory can do, but i am not sure if it will appear on client properly

Thnx for the reply Orange!

I was kind off expecting this. From what I've read online thanks for letting me know I was wondering what people thought who are more involved with developing Rust plug-ins.