Physical damage (PD) is more effective than magical damage (MD) in current game. One of the reason is the missing of physical resist (PR), while magical resist (MR) is >0.

My idea:
1. add PR to all creature (including player's characters);
2. the amount of physical armor (PA) and magical armor (MA) should be equal for most of the creatures, the difference between a tough physical defender (like a full armored warrior) and tough magical defender (like a pure magical creature) is they have higher physical resist (PR) or magical resist (MR);
3. when PA goes 0, half all MR; when MA goes 0, half all PR;
4. add one new talent called "armor breaker": if enemy has no PA, double damage to it's MA; if enemy has no MA, double damage to it's PA;

So the effective way to kill high PR low MR enemy:
1. break its MA first;
2. control it with magical status;
3. break its PA quickly with "armor breaker" to reduce MR further;
4. kill it with following MD.

A hybrid team could have one "armor breaker" with hybrid damage (like ranger with elemental arrows, or rouge with Chloroform/Gag Order skills, or mage with Necromancer+elemental skills);
Or 2 "armor breaker", one pure MD, one pure PD;

Pure PD team is hard for the game, blocked by some high PR enemies; while pure MD team still possible, since there are 5 types of MR, can focus on the lowest one.

I believe this idea can balance the game, introduce more team build, and increase the fun of battle.