For what it's worth, here are my thoughts on P3/Lexi Lightspeed after playing it at SFGE a couple of weeks ago.
I only played 1 game, so I did not get to experience much of the gameplay. What I did see of the gameplay was pretty neat. Seeing things like smoke trails from the ball on the LCD screen was a new experience. I wasn't playing it to see what Lexi Lightspeed was like though, I was playing it to check out the concept of having a ball tracking LCD as part of the playfield.
The platform wants to be a pinball machine, but is definitely not a video game. I think it might have more success as something entirely new. A lot of this is off the cuff, so some (or all) may not stand up to scrutiny.
The LCD concept feels like it is being held back by the need to hang onto things like slings, outlanes and inlanes. Come up with a new experience down on the bottom of the playfield as well, other than just the LCD. Why not eliminate outlanes in the traditional sense and redesign the apron so the flippers become part of the apron area versus a very industrial feeling linkage apparatus.
Make it more than about the traditional pinball game. Go on a bender and play Mario Party for 2 days straight then write some mini-games on the platform. Make it a competitive thing. 4 player mini-games somehow tied to pinball skill.
Again, just brainstorming, so you may have already thought of this stuff and I'm thinking I discovered the gas engine.
tl;dr - The P3 has a lot of potential, but I think it's limited by the desire to make it a "real" pinball machine. What is a real pinball machine anyway.