Natamycin is my nystatin substitute. I'm not sure of the extent of its effects, but I have noticed that I get worse every time I run out or skip a couple of doses (it's sold in a majorly incovenient and somewhat expensive 20-pill bottle, to be taken 4x per day, so it always runs out more often than other pills).
As to hard on the liver - it seems like the die-off, not the RXs themselves (except ketaconazole and IV amphocetrin), is what goes hard on your liver. At least from my own observations...
Terbinafine + itraconazole/fluconazole hasn't been studied much in humans as a combo, but it's used in veterinary care and agriculture a lot for resistant strains of fungi. Some sources do claim that you don't need much terbinafine at all for it to work, so maybe splitting pills is an idea. Apparently, this supermove manages to be fungiCIDAL against stuff that neither terbinafine nor azoles are even fungistatic against.
Terbinafine+fluconazole seems a bit taxing on your energy (I'm blaming fluconazole), but terbinafine+fluconazole (brand names Lamisil & Sporanox) seems a decent combo.
As to terbinafine's activity against candida, seems to help, plus the Russian version of the FDA has approved it for that.
I've been taking this protocol for over a month and I'm still here, after all. And, hell, Novartis even managed to get terbinafine oral approved for children age 4 & up by the FDA recently. Can't be *that* nasty, then.