Most decks run both if theyre aiming for that win condition, but Exsanguinate is positioned much better in the current metagame, where gaining life can often grant you another whole turn that you wouldnt have otherwise had access to
Best of all, Innistrad Remastered has dropped Laboratory Maniac's rarity down to uncommon , so maybe you'll be able to grab one without needing to forgo that grande cappuccino
You could easily say the subject of a card shouldn't be so diminutive in the card art, but I think she stands out well enough, and find this version a great fit for Innistrad, which is a perfect example of a 'Points of Light' type setting
The most obvious answer beyond that was seeing what rare or mythic rare you opened, or if you found that key uncommon or common for your deck
Otherwise, you'll be sitting on a triple version of your general, meaning your opponents will likely have to spend three times as many interaction spells to clear all of them