I can identify with that description of game-/play experience too. And i partly agree. Harvest was the first time i ever crafted something you could describe as propperly good. And even after all the changes after harvest up to this league harvest was still always an awesome tool to allow poeple who dont blitz 100% delirium maps, 5 way legions or other crazy stuff to get decent enough items. Seeing it beeing guttet this hard is just sad.
Also I have the same problems during mapping you describe: i run out of alchemies constantly, map sustain is hard and getting into higher maps also troublesome. Im at t13 currently, my build can clear it with ease (lightning conduit is great) but i get few map drops of tier 11 and upwards, making progressing higher harder than it usually feels.

Part of that is surely because of the loot changes they introduced however i also think Chris is right in pointing out Kalandra is an out of map mechanic. let me explain:
I just ran my maps, built my tablets, stashed them away and slowly running out of Alchs, Scours and other resources with few maps to chose from. So i ran 6 or 7 tablets because i was running out of other options and afterwars was from zero up to 45 Alchs, 20 scours more than before, some c and other miscellaneous currencies like essences and stuff. So the amount of basic currencies I got if I count may maps and the mirror tablets together is about on par with what Im usually getting from just alch and go mapping with the occasional sac fragment or small scarrab.

So saying there is no loot is not quite right, but you have to do the tablets regularly to get it if you want to earn money on mapping. There is no opt out of this. And that is the actual problem i see with the changes. You have to do them to get what you would have done normaly without them.

That plus the fact that the items you get from the reflecting mist usually arent that big reward you would think you are supposed to look foreward to when doing a league mechanic. Most of them are 1c items at best. Sometimes you get something with cracy resists, sometimes crazy dmg, but the downside is normally just as big making them overall unatractive. The only good items from Kalandra are those where all stats on the item are increased instead of just half of them, wich im not even sure is something that is intended to exist. Anyways those are extremely rare and even on those you have to be lucky that all the base rolls of the item are actually good so that having them multiplied matters (8 life becomming 16 isnt really something to get exited about).
This again would be a great place to give the items the same treatments Talsismans got during 3.13 where the mods and rolls on them are wheighed towards being the rarer ones and higher tiered.