Plasmas seem like the obvious solution but in the long term they do outgas. And it's not just the 128x32 displays that helped form the decision to go LCD, it also started with an outgassing large Sega DMD (which is the last working one we have) and a burned out WPC display driver board. I bought a $15 rebuild kit and as soon as I started replacing stuff the board was literally disintegrating from 20 years of heat. It didn't take long to figure out that plasma is not a long term solution, at least not for us. That would require at least a piggyback power supply (or a new driver board altogether) not to mention a new $150 plasma to go with it, talking on a game-per-game basis. When you figure the total costs it's pretty spot-on with $250, and the benefits of modern tech (and not to mention color) is a solid investment for any route operator. And what's better is that same fried DMD board is running in my example. The logic stuff is still good. Ever since I got back into this hobby I've made quite the effort to improve our fairly bleak situation as operators. This includes minimizing costs to keep our games running for years to come, and going LCD makes a lot of sense. If it's not a DMD going out, it's a driver board or some other high voltage issue.
It looks like people are looking for an "in the middle" solution both cost-wise and functionality-wise. I think you're on to something with a more basic kit. A good price point would be around $300. I'd say go for it!