Answer
On the first option, TL2000 already has a web edition that put configurable screens, mouse support, dashboards and mapping over the original IBM i application, so an ugly 5250 screen is a solvable problem that does not require touching the rating engine. On the second, Trimble owns both the TL2000 and Innovative Access Plus lines and has offered subscription versions of them, which is worth asking about if your issue is the licensing arrangement rather than the software. The third option is the expensive one, and it is only the right answer when the current system is genuinely wrong rather than merely old. If the driver is that a competitor has a nicer screen, start with the screen.