Once they let Summoners summon Shiva but rather than doing the cool thing - using the WoL as a vessel so that we transform into Shiva and we can play as Shiva (with a new non-Ysayle, non-Ryne model) - they just let us summon her as a lame external entity just like every other summon and with Ysayle's model.

When that happens I know the devs have become out of touch and no longer care. Shiva has never been an autonomous summon in the story and so she shouldn't be for Summoners either.