I have to be short, but:
1) Drop test will not be influenced, different reagents just turn to specificic color at certain pH.
2) EC going up with alder cones and ketapang leaves is perfectly ok, these are the substances you want in the water, it is just concentrated so you need to learn to work with that. Just find out how much of how concentrated extract you need to add in to certain volume of water. EC helps you track this. Have a look at my reciepe for paro water, you can follow simmilar scheme.
As far as peat goes, there are many types of it and some lower quality peats may release for example to much of fulvic acids at the beginning. However, no need to bother with that. What you are mostly interested with peat is not what you are able to leach out as simmilar (and even better) substances are easy to obtain elsewhere. It is much better to work with the kation exchange capacity of the peat, that will help you acidify the water much further. But it is not needed too, in case we need we are able to find some high kapacity katex that would do the thing.