Hopper allows you to change the representation of numbers in the disassembly window so that:
0000be84 str r3, [r11, #0xfffffff0]
0000be84 str r3, [r11, #-0x10]
This doesn't carry over into the decompiled code though:
r3 = *(r11 + 0xffffffffffffffd8);
Whilst it's not a major thing, it would be nice for the representation to be carried across.
Can this be done?