I need more time on JPOTC, but JP2 is perfection from a rules perspective and the game's layout is just the right amount of challenge for the depth provided. It feels perfectly balanced and games are short/medium in length. Most of my games are 6-8 minutes in length and my better games are 15-20 minutes. I think you could accomplish pretty much everything in the game in under 30 minutes. This is crucial for me having young kids and not a lot of dedicated/uninterrupted time for pinball.
For me, I've owned and have loved several of Keefer's Stern titles (LOTR, TSPP, WPT, WOF), but I think some of his more recent JJP games like Hobbit and JPOTC are almost too deep and convoluted and ball and game times skew really long.-especially on Hobbit but I've had some marathon games on JPOTC as well. And once you stack more than 2 things together it starts seeming like overkill. I love the layout on JPOTC and the ship is probably the coolest feature on any game I've ever played, but the vast number of modes just kind of seems "samey" after a while and the game seems like it's about stacking as many of the multi-balls together. It probably would be a good game to own at home if I didn't have young kids and had more dedicated pinball time to delve into the rules and not have to worry about 30+ minute games and getting interrupted constantly.
It might be worth reaching out to Karl iepinball since I know that he owns both games to get his opinion.