I jumped the gun on this a little bit and playtested Production Village before I even knew for sure that it was going to be the winner. I haven't had a chance to playtest it in a game with another human player, but I did implement the card in an A.I. and played a few games against that.
First two games were disappointments, despite that I set the first up with non-drawing terminals to set it up. It played like an ordinary Village most of the time. The problem is that I wasn't able to make use of its power unless I had sufficient density that I'd have two in hand, and then I only saw it on the second play. For example, in a hand of PV, PV, Woodcutter, Navigator, X:
- Play PV (draw 1 card).
- Play Navigator.
- Play PV (draw 2 cards).
- Play Woodcutter.
So when they collide together, you get an average of +1.5 Cards instead of +1 Card apiece. It isn't enough to make a Village tree with weak terminals a viable strategy, because you still need drawing to get enough actions into your hand to play them, but if you draw in any other way than the PV's themselves, you'd be better off playing with vanilla Villages.
I don't remember which actual terminals I used in that first game, but among them were a mix of strong (Mountebank) and weak (Woodcutter, IIRC) ones. Anyway, my conclusion was that on this kind of board, PV wouldn't be worth going for unless vanilla Village was. And on that specific board, it wasn't, so PV wasn't worthwhile either. I'm not even so sure that Mountebank, strong a card as that is, was good enough. The presence of Mountebank just means that you'll be getting junked up too, which means the chance of getting PV-PV-Mountebank-Mountebank hand is slim.
Second board was a more random mix, and I couldn't find a place for PV either.
Third game, PV was a jawdroppingly powerful superstar. The key card in that game was...Goons. PV+Goons was amazing in two ways. One, Goons is THE non-drawing terminal to try to play multiples of with Villages. So not only is that something you want to try to do, but the fact that Goons doesn't draw means that PV is the best Village to do it with. Goons also covers several other key engine components such as +Buy (so using Worker's is less important) and $ (so using Bazaar/Festival is less important). There was a trasher in the kingdom too, so I was able to clear out the stuff that kept my PV's and Goonses from colliding.
Two, PV is THE defense against the Goons attack itself. Having to discard down to 3 cards in hand is probably actually a benefit, as you can discard weak cards and perhaps draw better ones when PV gets you back up to 5. Unlike Watchtower and Library, using a PV to draw back up doesn't consume an action.
One might argue that this is too strong a defense, since it actually helps you to get hit by a hand-size attack. Well, I dunno. It's not dramatically stronger (if at all) than Trader vs. Curser, for example. It's just a really good combo. Against other discard attacks, the defense may or may not be worth going for. On some boards, you might not even want it against, say, Militia: it's the fact that Goons is a must-buy almost every time Goons is on the table that makes PV, in turn, such a powerhouse in combination.
Finally, to speak more generally about non-terminal "draw up to X cards, probably the fan card I've tested more extensively than any is my Archivist card. I'm pretty convinced it's balanced. But there's no question that PV is the more situational of the two, ranging from "weaker than Village" to "probably a must-buy" from board to board.
Although they didn't come up in my test games, it occurs to me that buying this card opens the door for your opponent to go for Council Room. For example, say you have a PV in your hand. You'll probably play it first next turn, in which case you'll draw a card. But if your opponent plays Council Room, you draw that card and then don't draw an additional card when you play PV on your turn. Well if you're gonna get that card anyway, then your opponent's Council Room has no benefit for you -- so he gets his +4 Cards, +1 Buy for free!
Finally, one more combo that didn't come up in my test games: Hamlet. On the surface, Hamlet is a good enabler here. Discard stuff with Hamlet, draw replacement cards with PV. I have a sneaking suspicion that as cool as this sounds, it's a nombo. The problem is that PV gives you extra Actions, but if you have a Hamlet, you're already getting extra actions. So all PV is doing for you is providing replacement cards that your Hamlet gave you. Is that so much better than Worker's Village+Cellar? You do end up a card higher with Hamlet+PV (though WV+Cellar lets you replace more cards if desired), but I suspect this is still a Village Idiot-style pursuit. You don't want to load up on Hamlets and PVs just because they power each other up -- there's got to be something more to the picture.
Anyway, my general conclusions: I lament that the card perhaps doesn't shine all that often; that said, I think there are tons of cards much narrower than it, and it works even if you can't pair it up with power enablers. Based on what little playtesting I've given it thus far, I think it's a good card, balanced enough, and correctly priced.