Helmets:
The Helm of Command These will be the BiS for barbs and most likely monks due to the rolls of %life, % block, res All and Dex/Vit/Str.
Mempo of Twilight will be a PvPer helmet due to its high percent of cc reduction, % life, and attack speed.
Andariel's Visage is one of the most widely used helmets in the game at the moment. High attack speed and crit chance + chance for a socket, % life, and high base stat.
Chest:
Tyrael's Might Chest with movement speed (movespeed) increase and damage increase to elites.
Beckon Sail Top chestpiece for Demon hunters due to high Increased Attack Speed (IAS) and crit chance increase. Can roll 0-3 sockets for huge Dexterity bonus.
Tal Rasha's Guardianship IAS on chest and a set bonus of (2) 3% increased fire damage, (3) 3% increased lightning damage, and (4) 3% increased cold damage.
Pants:
Inna's Glory IAS, movespeed, and crit chance.
Jewelry:
Justice Lantern for extra %block.
Natalya's Mark IAS + high base stat rolls and use of Set bonus.
Flavor of Time like OP stated IAS, movespeed, and CC reduction on a neck. PvP neck for sure.
Mara's Kaleidoscope decent tank neck with reduction from melee/ranged.
Off hands:
Storm Shield for the % reduced damage.
Ivory Tower is another decent shield that can be used for its damage reduction and its chance at high % life.
Black Bone Arrows for % damage against elites will make farming quicker for DH.
Dead Man's Legacy is another quiver. This differs from black bone in the fact that it can give % increase to some of DH strongest abilities along with a chance for the highest % attack speed on quiver.
Uhkapian Serpent is BiS for WD due to its chance at max off hand damage, % damage against elites and chance on roll to give % damage to certain WD spells.
The Oculus like the WD mojo this can give specific spell % increase as well as being able to roll high Int and top damage on a source.
Belts:
String of Ears for the % melee damage reduction.
Boots:
Boj Anglers Increased attack speed and movespeed with cc reduction. These will be pvp boots in my eyes and can be fitted to any class.
Zunimassa's Journey Increased attack speed and movespeed.
Fire Walkers Reduced melee and movespeed.
Natalya's Soul Reduced melee damage and movespeed.
Bracers:
Lacuni Prowlers These are extremely powerful at the moment for an increase in movespeed to hit that 25% everyone wants and IAS which is a straight damage increase. Even better is these can proc magic properties to make them beneficial to all classes.
Weapon:
The Three Hundredth Spear, The Gidbinn, and Sunkeeper all %MF weapons for you and your Companions.
The Official Brady Games Diablo III guide says this about the loot system.
"If a monster drops loot, the quality of the item(s) dropped is most affected by the monster's level. If the loot bursts from an environmental object like a chest or barrel or pile of bones, the type/quality of items is most affected by where you're at in the game.
Other factors can come into play, as well. The fact is, Diablo III monsters can drop a wide range of loot items, but the odds of a low-level monster dropping a high-quality item are extremely small. So overall, it works just as you'd expect: The higher a monster's level, the better chance that it drops good loot after you slay the beast."
It also goes on to say;
"Again, there are ranges of quality for both the base item and for any affixed special properties. As we said, the primary variable that determines the quality of a slain monster's loot drop is the monster's level----the higher the monster level, the more the odds are weighted in favor of it dropping a higher quality base item, and the better chance that the game will also attach higher quality enhancements (or "affixes") to that base item.
These item/affix ranges are divided into "tiers" that correspond to the monster levels. If the monster is a low-level creature, chances are that any gear it drops will be selected from the lower tiers of items, and enhancements assigned (if any) will be from lower-tier affixes. Thus, each monster is said to have a "treasure tier" based on its level----the game tends to drop random items selected from item/affix tiers that correspond to the monster's level."
This is why the patch notes you quoted say "The new approximate drop rates are as follows" since drops from mobs are not based on act but monster level.
When I have some time I'll compile a list of the level ranges for each act/difficulty since the guide does have a complete list of the bestiary complete with monster levels.
To be honest I think you're over thinking it a bit. If you're level 60 then you should be farming the highest act you can reasonably do no lower than act 3 Hell mode and if you're lower than level 60 then farm the highest act you can farm efficiently. Farming one act back from whatever act is giving you trouble will give you a chance at gear you can use.
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- Act 1 has ilvl 61 mobs
- Act 2 has ilvl 62 mobs
- Acts 3 & 4 have ilvl 63 mobs
There are some higher (and lower in act 2) level mobs in both acts 1 & 2 but not many. Act 1 has one ilvl 63 (spiderlings) for instance.
Best Answer
Twinking
"Twinking" is the general term for giving items to lower-level characters who can make better use of them. Many will be usable by any character you create, but occasionally, there will be some items (class-specific ones, in particular) that won't be useful to any of your characters if you've got a high-level character of that class. If that happens, just give it to a friend or sell it off in the Auction House - there isn't much point to keeping those, except for...
LLD (Low-Level Dueling)
In Diablo II, PVPers came up with a concept called Low-Level Dueling. They'd set a max level limit for the characters, which also limited the power level of items you were dealing with. If/when PVP is added to the game, LLD may become popular again. If that happens, there may be some low-level items that become particularly valuable, just for the fact that they are very powerful for their level requirement.