In the first game, ships repaired themselves over time when in friendly space even without repair modules, same for armies in Legends. I don't know why that was taken out.

I can get behind your hangar repair idea, but I don't think it should tax a system's industry just for being there. However, having a Convert Industry to Ship Repair thing sounds like a great idea, especially for those poor little warmongering races, crippled by fleet upkeep. Cravers don't suffer from it too much right now, especially given their government bonus to dust, but I can remember how I struggled with finances mid game when playing Hissho in ES1.

Two good ideas here!

Like Trentius I don't know whay this feature has been removed, but anyway for me is not game breaking as long as they mantain coherent costs for ship repair.

Pretty much every 4X game ever has a way for units to heal themselves slowly overtime.  Even if it's just 5% or 10% per turn.   Maybe consider this:

1. Units garrisoned at a friendly world heal 5% of their health per turn for free.  Tech's could be added that repair this speed.
2. Repair modules allow ships to heal themselves by whatever amount regardless of where they are located.
3. You can pay dust to insta-heal ships at your owned systems as you can currently.