Currently, everything in PAIR uses coding frames to serve data. This is why all of PAIR has a single URL, why opening a two PAIR windows or two EFS windows doesn't let you do two things in parallel, and why you can't refresh or navigate forward or backward without it going haywire.
Instead of the current setup, switch to a page-based, rather than frame-based, architecture.
This would have tremendous benefits. Pulling up information from several cases at once would make things tremendously more efficient for everyday checks on cases, or for being able to better correlate or compare information from different cases.
Or consider those times when you need to file the exact same package in a number of different applications - large parallel IDSes with many foreign and NPL references, for example. Instead of having to attach the full package in one, then in the next, and so on, you could have several tabs open, each with one of the applications, and make sure that all of the filings have the full set of documents.
If, as has been suggested numerous times here and elsewhere, the PAIR/EFS authentication system were changed to something not using Java, this would seem to dovetail well into that upgrade. At least some of the core system functionality would need to be changed to implement a new authentication scheme, so it would seem to make sense to use this as part of the resultant new architecture.
I fully realize that this would be a long-term goal, as it would require a major overhaul of core functionality and would be neither cheap, easy, nor fast, but it would absolutely be worth the wait.