My suggestion to this after giving it some thought is that some of the spells, namely bless weapon and holy weapon should be changed a bit in level if they should be included in the layo crafting system.
Bless weapon should scribe around level 3 or so depending on its duration, if it is three minutes(cast as level 3 which I think it is) it would be too powerfull as a level 1 scroll.
Holy weapon, the thing that drops is level 17 so it gives you 17 rounds with a +5 blade which is not overly powerfull but surely too powerfull for a level 4 scroll, my idea would be to either make this level 6 or maybe even 7 to reflect the power of this.
Deafening clang is another good spell, but seeing the low caster level on a potential scroll I would say that level 1 or maybe 2 would be high enough for this spell +3 sonic damage is neat but if it only lasts around 3 rounds it is not overly strong.
