Here is how I would fix itemization issues to make classes more balanced
3400g -> 3600g, 70AD -> 75AD
3400g -> 3600g, 70AD -> 75AD
2600g -> 3000g, 35%AS -> 40%AS (shiv and rfc passive will no longer stack)
2600g -> 3000g, 30%AS -> 40%AS
2600g -> 3000g, 40%AS -> 45%AS
2600g -> 3000g, 45%AS -> 50%AS
2400g -> 3200g, 40AD -> 60AD, 30Ar -> 40Ar, (This is way too cheap for its game changing passive)
3500g -> 3300g
3500g -> 3300g
3700g -> 3600g
3733g -> 3600g
3000g -> 3100g, 40AD -> 45AD
3800g -> 3600g
2900g -> 3000g (This is a little bit too efficient)
2600g -> 3200g, 300HP -> 500HP, 75AP -> 80AP (Better for battle mages, worse for supports)
2700g -> 3100g, 300HP -> 400HP, now gives 1% cdr per stack (up to 10% cdr)
2900g -> 3200g, 70AP -> 100AP, 10% cdr -> 0% cdr (it should be a high ap item like it used to be)
2900g -> 3300g, 55AD -> 65AD (This is too cheap for the powerspike it gives)
2900g -> 3200g, 55AD -> 65AD
3100g -> 3300g, 15MPen -> 20MPen
2600g -> 3000g, 35% BonusArPen -> 45% BonusArPen (tanks get way too much armour nowadays, especially with aftershock)
2600g -> 3000g, 35% BonusArPen -> 45% BonusArPen
2650g -> 3000g, 80AP -> 100AP
18MPen -> 15MPen
removed from the game
With these changes, adcs will now have to pay 9600g for the triple crit instead of 8600g, but will be slightly more powerful.
Bruiser core
will now be 10100 instead of 10433.
With my changes all completed damage items will be 3000g - 3600g, while tank/support items will be 2900g or less