
In my case I'm making Ultimate File Manager being able to run from ROM. MooingLemur requested to not use basic RAM. So all data and variables need to be in $0400-$07ff or in a rambank. This requirement will probably be the same for future programs that will be included in rom aswell.
I would suggest there needs to be some agreements on when and how to use the non-basic ram between different ROM programs.
For example: parameter exchanging is best handeled in the $0400-space. Therefor if an inputparameter is needed for a program in ROM it should first read/use all inputparameters, before overwriting the $0400-space. I recon it is a small adjustment which can eliminate these kind of problems in de future.