To make survival harder (not by adding zombies more HP), I would be happy to see advanced illness system. A little complicated but still clear. E. g.:
1) If you be too cold, you can catch a cold
- stamina regen
+ noise
2) untreated cold turn into fever...
- max health
-- stamina regen
- max stamina
+ noise
(being wet makes easier to catch cold)
2) ...or/and sore throat
- max health
- stamina regen
3) untreated fever turns into infection
-- max health
-- stamina regen
-- max stamina
- running speed
+ noise
- weapon handling
- bows and crossbows rate of fire
4) untreated fever turns into heavy infection
-- max health
-- stamina regen
-- max stamina
- running speed
+ noise
- weapon handling
- bows and crossbows rate of fire
- x health/minute
* food don't heal
5) being exposed on sun too long cause sunstroke
( hats give more time )
-sth
6) bite by zombie cause zombie infection
-like now
* 80% cause fever
7) burns (after contact with fire or long expose on sun)
- max health
8) being too long in high temperature cause dizziness
-- fire accuracy
1) If you be too cold, you can catch a cold
- stamina regen
+ noise
2) untreated cold turn into fever...
- max health
-- stamina regen
- max stamina
+ noise
(being wet makes easier to catch cold)
2) ...or/and sore throat
- max health
- stamina regen
3) untreated fever turns into infection
-- max health
-- stamina regen
-- max stamina
- running speed
+ noise
- weapon handling
- bows and crossbows rate of fire
4) untreated fever turns into heavy infection
-- max health
-- stamina regen
-- max stamina
- running speed
+ noise
- weapon handling
- bows and crossbows rate of fire
- x health/minute
* food don't heal
5) being exposed on sun too long cause sunstroke
( hats give more time )
-sth
6) bite by zombie cause zombie infection
-like now
* 80% cause fever
7) burns (after contact with fire or long expose on sun)
- max health
8) being too long in high temperature cause dizziness
-- fire accuracy