Pia's Revolution is a powerhouse of a card.
I said in my last update that it seemed like a 'win-more' card and not something that would be a mainstay in the list. And in several situations, I think that this is the case. However, that being said, it was won me more games these last four weeks than Galvanic Blast ever has.
For instance, last Friday I was precisely two turns away from being taken down by a hefty Goyf and some Lingering Souls tokens. I had done the maths based on my board position: 1 point away from lethal with infect, 1 point away from lethal with regular damage. I needed a way of doing that extra damage. Pia's Revolution came to the rescue! "Sac my Mox Opal, trigger". If he gives it back, I get lethal with Inkmoth. If he doesn't give it back, I have lethal in damage. He conceded almost on the spot.
Situations like this have happened at least once every FNM since I came back with robots. It feels incredibly saucey.
It might still only be correct to have two in the sideboard; I almost always find myself siding one out and it generally doesn't do a whole lot game 1, either through a lack of finding it because the games end so quickly or because I don't end up needing to cast it (again, because the game is over). But games two and three, it does serious work. I'm not sure what room to make, but for now I'm sticking with three in the main. At the very least, it's super fun.
Lots of people have been asking me about Spire of Industry. The idea that it is 'strictly worse than Glimmervoid' is, I think, a relatively well-supported point, but I'm not sure that 1) it matters at the local FNM level or 2) that it's actually the case. I almost exclusively find myself tapping it for colorless mana, and not having to worry about leaving mana up to animate lands at the end of a turn because of an inconvenient Recall is quite the relief. I'm not sold that the one damage actually matters, although it might offer marginally better percentages in the long-run. I know that most of my matches have never come down to me wishing I just had one more life to survive an attack or a spell. But maybe that's just because I'm not a Pro. For now, at least, it's staying. And I'm enjoying it.