Currently, in the Engineering system, crafting Sun Scrolls requires 10 Runic Blueprints. At the moment, this conversion is working, but it is already close to the practical limit of Runic generation.
Right now, I can generate around 164 Runics per hour, while my Sun Scroll generation is around 14 per hour. However, increasing Sun Scroll production is relatively easy by supplying more wood and ore, which means it can quickly surpass the current Runic generation capacity.
On the other hand, increasing Runic production any further becomes extremely inefficient. It is still possible to push it a bit higher, maybe around 175/h, but the material and gold costs become unreasonable very quickly.
My concern is not the current situation, but the future progression of the game.
Once the last 4 mobs from Act 3 are released, along with the material-based upgrade system, Sun Scroll generation will likely increase significantly. As a result, the demand and consumption of Runic Blueprints will also increase considerably.
I believe this is something worth evaluating in advance. Right now, it is not a major issue yet, but I think the balance should be reviewed before this next stage of progression arrives.