It seems to me, that you need to edit the pointer table to read 24bit instead of 16bit.  In my exploration of roms, any 16bit pointer will (for the most part) land you within the x0000-FFFF range that they are in.
by increasing the tables by another 8bit hex character, it allows the pointers increased range of x000000 to xFFFFFF.  giving you the ability to turn the pointer for "5E70" to 00 5E 70 letting you know it is near the front of the rom at x00B05E, or maybe making it 02 5E 70 or x02B05E. (where all your open space is in.)

It might be complicated a bit, I know there are some pointer hacking documents on this site, but I'm not sure if any of them properly cover how to convert pointer tables from 2byte to 3byte, and I don't know if I'm competent enough to explain how to do it.  Perhaps one of the gurus here could help more...

Thank God the Sylvanian Families games already have support for this...>_>

Not always. MBC1 and 2 handle things differently I hear.
Most games do have code that get's 1 byte out of another rombank. It goes something like this:


So that would give the resulting byte in a. The actual code at fb4 might differ a lot, however, many games use rst $10 and rst $18 as swap banks and reverse (respectively), just look for these kinda things in some code you know has to access widely different data. Or, you could just write one such call your own

cYa,

Tauwasser