Quote from Bagstone
It's not just a simple formula. The problem is that legendary items have certain fixed stats neglecting the "level <-> stat range" rule. For example, look at Mempo or Andariel's. There are so many fixed stats and affixes that roll on a slot they usually wouldn't be available. In particular, the 4.5% crit chance on Andariel's is fixed, it's not just a range. Okay, now you might say "let's scale everything down", so it's just something like 1% crit for a level 30 Andariel's or 2% IAS, 1% crit, 15 allres for level 30 Mempo (completely making up numbers here). And same with Lacuni's, you would just scale the IAS and MS down, right? Well... but Slave Bonds also have 11% MS - on level 33. Do these scale up then when going to level 60? The problem is: how will they make sure that these items are well-balanced? They shouldn't become absolute BiS and killing diversity for this slot pre-60 again (drawing everyone to the AH to buy this item for their low-level twinks), and at the same time make sure that these items are useful. We don't want Witching Hour to be useless pre-60, but we also don't want it to be a must-have item (as it's now in endgame).
This balancing issue is what makes RPG game design so incredibly hard. It's not a programming issue at all.
Yeah of course. Didn't mean that one formula would solve anything, but it would help with the scaling of all the random affixes on items, which would take care of the "easy" 80% of the work. The hard part is indeed the scaling and balancing of the other 20%, e.g. the stats that make the items legendary. I'd much rather have that they take their time on this one than that they just say "level 10 gets 15% of the stats, period" (pretty much contradicting myself here, but it's early here, gimme a break :P)