You need to nail down your measuring technique. I messed up my first few recipes too - cuz I wasn't measuring stuff right. And with small batches, slight measuring mishaps are much more noticeable. Bigger batches will give you a bigger margin of error.I tried another smaller batch after but a different recipe. I started without nic and added flavor by the drop. I'm not going to say it was "good", but it was less disgustingI think the flavor concentrates are stronger than expected and adding more seems easier than cutting it until it's right, as with this first batch.
I haven't tried a larger batch.
Also be aware that your flavors, pg, vg, and nic base will each have a different number of drops per ml - thinner liquids tend to have more drops per ml than thicker liquids - and you might be surprised at how much difference there is. The same liquid can even have a different number of drops when measuring from different droppers or in different temperatures.
I suggest getting some cheap 1ml syringes. If that's not possible, try to find a way to measure the number of drops of your PG, VG, and NIC in 1 ml (do you have a medicine cup with 1ml marking? Or a dropper with 1ml marked?) The flavors should be about the same as the PG, ASSUMING you use the same dropper, otherwise you'll need to measure flavor too.