Should artificers be able to make Infusions permanent?

"you're on to something" .. which is just that there needs to be some mention of how to link their Infusions to the generic rules for creating magic items.

There's nothing unique about Artificers creating magic items.  The unique part is how to factor an Artificer's Infusions into that process, and maybe giving them some sort of advantage (not necessary Advantage to a roll, just some leg-up on it -- such as having it take less time) for crafting regular magic items in general.

Some ideas about those advantages that an Artificer might have when doing the normal Magic Item creation process:

• Advantage on any tool/skill rolls used in crafting any magic item
• Takes them less time to craft any magic item
• Maybe making an infused item into a permanent magic item doesn't require any special materials (other than the already Infused item itself) nor tool/skill rolls, just the same amount of dedicated time it would take an Artificer to make that magic item from scratch (meaning "without an already infused item").
• Adding an infusion to an existing magic item (not possible via the normal Infusion process) can be done via the general Magic Item Creation rules, but just that process of permanently adding 1 infusion to an existing magic item takes half as long as the creation process for that Magic Item.  So maybe you have a Light Hammer +2, but you want to make it a Light Hammer of Throwing and Returning +2, so you want an Artificer to use their knowledge of that "Throwing and Returning" Infusion to enhance your existing Light Hammer +2.  They can do it, for half as long as it takes to create a Light Hammer +2.  All of the restrictions apply EXCEPT any restrictions about adding an infusion to an existing magic item.