Range is 700 now and there are champs that do all or most all of their damage in range with the added bonus that teamates could be in range. The Aura is a nice bonus for the team, but if most all of a champs magic damage could benefit, then it seems to make sense. In this meta, most people are running high HP and lower resist, and that favors Abyssal as long as you dont drop them below 0 with your runes, boots, etc.
Eve, Diana, Mumu, Kassadin, Katarina, Fizz, Rumble to name a few all most of their damage within 700 damage and benfit from the MR in a good way. Hell, I threw it on Annie the other day since all her spells less than 700 range and they were weighted towards magic damage.