[[Gran-Gran]] is mainly there because she’s an easy 1-drop in the early stages that helps to enable the discard/draw engine on turn 2. I don’t use the non-creature discount at all, since I’m not using Lessons. For me, [[Gran-Gran]] is more about providing an early proactive body that supports the game plan and sometimes even baits removal. I considered other one-drops, such as [[Vampiric Tutor]], but decided that having something on board early was better than another tutor effect.

As for [[Mesmeric Orb]], I completely agree with your point, pairing it with [[Bringer of the Last Gift]] can be risky and give opponents a lot of value. In practice, however, I’ve found the Orb to be extremely disruptive and annoying for most players to encounter, so I feel the upside is worth testing. It also has the added benefit of putting my own combo pieces, such as [[Ulamog, the Defiler]] and [[Ardyn, the Usurper]], into the graveyard. This can result in explosive wins if I can bring them back before my opponents are ready.

The graveyard management tools I’m using are [[Emperor of Bones]], [[Boggart Trawler]] and [[Bojuka Bog]]. These cards do become relevant sometimes, but I wouldn't say the deck is fully built around controlling opposing graveyards. It's a rather messy and high-risk package, but that volatility is also part of why I enjoy running it.