A little more flexiblity and customization in ranks would be nice. I love the rank system, and would like to see more attention paid to it.
Some additional rank suggestions:
+skills
+hps
+spell damage
immune_bleeding
detect_astral
bash_mod
extra_attack %
auto_invis
immune_vorpal
free_action
immune_disarm
immune_magic
limit_damage %
resist heat/cold/elec etc (less costly, less effective than immune)
Also increasing limits on +stat. I know the max was recently reduced to 4 from 5, but I can't see any good reason for doing so. Obviously to place more emphasis on gear, but why? +4 stat is already 8rps.
Bonus: All 'non-rank' mobs give a rank %. .01% at least gives some meaning to killing things. At 10,000 mobs per