Oh boy, I hope it gets renewed, though I haven't much hope. Abe and Henry are the heart of the show and Lucas was fantastic tonight. I agree that I think Jo must have anticipated he'd act thusly?
There was a lot I think we were left having to assume that made it sloppy -- that with Jo and Lucas, Adam having the original gun (and as has been pointed out how the heck do they know THAT GUN is THE GUN, etc).
I will admit, I've always been a fan of Adam as a villain and didn't find him too cartoonish. That said, I think they wrote him into a corner, and upped the "cartoon" in the finale. I found it initially refreshing that he wasn't someone orchestrating EVERYTHING, as Henry initially suspected, and even in fact that with Abigail, his intent hadn't been to kill her. That said, the years clearly drove him insane and I'd venture destroyed any moral compass he had (I wonder if there was any consideration for there simply being different ideas re: morality 2,000 years ago). I thought his loneliness was a bit pathetic and thus pitiable. ...and also as for Abigail, lmfao what the heck did he think he was doing threatening with the knife, like... what a bozo. Also for not killing himself post syringe, but I guess he wanted to keep his stuff on him?? Why not stash em IDK??
Re: upping the cartoon, I also couldn't understand why he was suddenly needing to play a game rather than killing himself promptly. He'd been fairly honest to date. Was he lying the whole time? Never planned to kill himself? So what then? Just totally deranged? Just so lonely before and thus so obsessed with Henry that he had to keep that going, this little bright spot in his empty endless life? But, while what Henry did was cruel and necessary (and also again reiterating said concerns re: wtf happens when he DOESN'T AGE), it was also obviously necessary for the plot. I think Adam had the potential to be more interesting than he was-- a chilling 2,000 year old foil to Henry, not entirely "evil" but certainly awful, but his obsession was specifically the dagger/how to kill themselves/Henry by extension, but that wouldn't be sustainable. He'd have to go REAL cartoon psycho and that'd also have a short shelf life.
I skimmed the Miller interview where he says (if s2) they'll be introducing new characters who would dramatically shift the whatever, so I guess those'd be more immortals and Adam will be totes irrelevant, which is probably good, but it just feels like a waste of a 2,000 year old immortal character. Maybe in the unlikely even it's renewed we could get that slow turn/sit down and chat/Spike type deal... more likely they'd just make him extra psycho with fury @ Henry for what he did blah blah blah.
Sorry for the Adam spiel, been thinking about it and nowhere to put it!
All that said -- as bored as I am by these kinds of shows always hooking up the leads, and as rushed as was Jo's romance this season (such that it felt like a big hard push at Henry and subsequently clumsy), at least they're very cute together, so the inevitable romance in the event of a second season should be fine.