Glad to hear you got the electrode in place and have some pearling!
It does sound like the algae got a good foothold and breaking down the tank might not be a bad idea, and given that you aren't super happy with the hard scape anyway, it sounds like you have a new project on the way!
I am sorry to hear about the pygmy cories though! Gosh I feel lucky about mine then! I lost some in my 5.5g when i had a tank crash and i lost a few in QT before they went in my 30g, but the 6 I put in my 30g when i started it up are doing well...I was REALLY careful about the QT and then drip acclimating them to the new tank because i'd lost some before, but I imagine you're careful with those things too. Maybe once the tank is happy and balanced it might be worth trying them again, they are so darn cute!
But I also understand the frustration! I actually went to look for more the other day but the place I usually get them was out. Alas.
Can't wait to see the new direction this tank takes!