For a better look all the drop downs should be the same width. Using several for the line works best for me.
Several of these drop down lists are programmatically populated. The mod-set one can be pretty much any width as people can name their mod-sets anything pretty much. So it is not really worth extra effort to try to generate a uniform width.
Consider leaving the number of saving throws and modsets open ended and maybe have an add button to update the frame to include more.
If an AE needs to generate more than 2 effects, just run the tool again. The interface complexities to support that open ended flexibility are too great for the return.
I'm not sure why you have npc, pc for mod sets..Example
: Cleric Colodra casts Prayer. Generally speaking, the PCs will receive the beneficial effects while the NPCs will receive the detrimental effects (and there are two different mod-sets for just this situation).
I would have apply on save, apply on fail, apply always.
I like the idea of apply on Save vs. Fail, that is a keeper!
Maybe have a spot for user conditional code to be evaluated (ie if(Intelligence < 3,0,1) ) and have an AND or OR next to it. So, apply on fail: so Fail AND condition would be 0, so mod is not applied if Int was below 3. Just a thought.
This looks like a v2 enhancement