I don't think it's possible to have another PS:T, for several reasons.
- Production costs: Making a game today costs a lot more than at the time of PS:T. If they lost or didn't make money off it then, today would be just an economic disaster.
- Production specifications: I'm sure making PS:T took a long time to develop because of all its intrincacies. Well, that would be dwarfed by how long it would take today. To what they did, you now have to add: 3D modeling, 3d exploration, voice overs, more complex special effects, etc. What they did with 30 people now would take 100. To recover that you would have to be sure that you have a huge ...
- Audience: For the game to even break even, considering the costs, it would have to sell like 5 times more than what the original sold... and I would be surprised if it even matched the original's number. Let's face it, gamers today want more flash than content, and PS:T was all about content. It would also be a poor candidate to go cross platform because their audience is even worse in that aspect.