+20 health per second would be balls-out insane on the charm of life. It should be +10 tops. you've gotta realize it'd be +400 health in just 20 seconds, ignoring monks, it'd catch up to BotF within 26 seconds and outpace it dramatically afterwards.
although we are trying to balance out all favor items strengths. but +10 or +15 would be nice for charm. some tweaks i would do..
Bejewelled goggles (meant for ranged AA characters)
+12 vision radius
+3 attack range for ranged characters (dunno if thatll be hard to do or not)
Brilliant Bauble
+20% exp
+4 gold
Symbol of Purity
Reduce cooldown to 25 secs
+300 max health
You recieve 5% less dmg when debuffed.
Staff of the Warmage
+600 mana
+20 attack
+5 mana regen
Crimson Vial
As it is now but...
Reduce 'use' cooldown to 30 secs (15 secs less than it is now)
Diamond Pendant
+500 max mana
-10% ability cooldowns
Use
Cooldown: 30secs
The next item/skill activation you do, recharges 20% faster. (stacks with the passive 10%)
Cape of Plentiful mana
As it is now but...
Reduce cooldown to 35 secs.
+4 mana regen
Wings of the Seraphim
As it is now but...
Condition of negating this buff should be change to "using a skill will break this effect".
Mards Hammer
+40 dmg
+10% attack speed
Use
Nearby allies gain 10% attack speed for 6 secs. (does not apply to you)
Staff of Renewal
+600 mana
+6 mana regen
-20% cooldown
Essence of magic
as it is now but...
Reduce cooldown to 30 secs
Furious blade
+10% attack speed
+5% vamp
15% chance on hit to increase attack speed by 30% for 5 secs
not sure for general favor items as i dont use em often...