Half-elf Dilettante enhancement question

[cybred]

Under the caster enhancements, it states that item use level is increased, other than wands and scrolls what effect does it have?

[FuzzyDuck81]

Short answer, nothing else - it doesn't effect the caster level of scrolls & wands, but what ones you have reliable access to as an honorary member of that class.

Longer answer:
So long as your class has a certain spell on it's spell list at all, a wand will have 100% proficiency in casting it so long as you meet the minimum level of the wand, even if you only have a single level of the class, which is what the basic dilettante feat grants you. To use a scroll, you have to have the minimum character level to have a chance activate it at all, then that success chance is based off the number of class levels you have; if you have sufficient class levels to cast that spell natively from the spellbook, it'll be 100%.

A good example is Heal. Spellbook based casting access is at level 11 for clerics, level 12 for favoured souls & 15 for druids. A Heal scroll is minimum level 9 to be used. You lose success chance for each class level below that, so 10 cleric levels (which the cleric dilettante enhancements will go up to with the full line) will result in a 95% success chance. A level 7 spell scroll eg. greater restoration will be ML11 to use & requires 13 cleric class levels to cast from the spellbook, so having an equivalent of 10 cleric levels will mean you're 3 levels below & have a 75% success chance (it's 5% less chance to cast for the 1st level below & an extra 10% for every level below that due to how the calculations work). Meanwhile, a level 5 spell would require 9 cleric class levels so with full investment in the dilettante line, they & anything lower will have a 100% success chance.

The success chances aren't linked to UMD at all so they won't change - good UMD investment will boost it higher (as the highest success chance will apply) & is almost always better, but the flipside is that since they're not linked to it & won't change, you won't have to worry about negative levels tanking your ability to use them. Side note, this means that something like eg. a dragonmarked gnome warlock can actually use Heal scrolls with 100% success chance straight away at level 9, when even clerics will fizzle sometimes.