I think this game has made some great improvements since Senyuu Danshi and I really liked that game as well.
Having said that, I don't know if this is a bug, I'm just having bad luck, or if it's working as intended but the drop rate for blue jello is abysmal. Other than the first two I got from the intro, I didn't get a single blue jello for the first 10 slimes I defeated or so... Pair that with the power of slimes, they basically knock you out in two-three hits, makes the third part of the intro questline tedious and waaaay harder to complete than any other quest so far. The fact that I need to raise my charm to 3-4 levels to reliably defeat slimes in order to only get about 1-2 jello/excursion feels bad. Then the fact the crafting is basically gated behind this quest is not fun. Is the recipe for empty bottles are part of the crafting reward`? Because that makes it even more tedious, since you can't heal effectively either. I think I've made about 20 or so excursions and I've only got 11 jellos now.
My suggestions (unless I'm the only one experiencing this and just have crap luck) is to either:
1. Make slimes attack less powerful and/or lower their health a bit.
2. Significantly increase the drop rate or at least as long as the quest is active (don't know if that is possible to code)
3. If your satisfied with the difficulty, I think you should consider renaming this last part of the quest. Having a quest called intro quest and then being harder and taking longer than a bunch of other early fetch or drop off quest is a bit ridiculous and counter-intuitive.
Sorry if I sound rude, I'm just a bit frustrated. Anyways, keep up the good work! :)