I remember times leveling my alts and the quick transition form the previous expansion to the next being kind of a pain, with the difficulty when in comparing ilvl, where u had to be very careful with how completing your first quests and acquiring your first pieces of new gear considering how powerful the new mobs were and all that.(Now this is for those characters that have little to no heirlooms or dont want to buy lvl 100 boost)
So lets say im leveling a character the old fashioned way through the Draenor content, whats the approximated item level good enought to transfer to broken isles starting zone, without it being too hard? Can you go there with Ilvl 620 average, or do you have to spend time in the Tanaan to get baleful gear for example?