This seems useless.
We'd disable all the PvP aspects, so health, food, equipment. You can already see everything in regards to dropped items, hovering over it in your bag shows it's enchantment, name and durability. You can identify owners of animals with I believe McMMO, villagers are identifiable by their skins an items they sell, and I'm quite sure we all know what mobs are aggressive by just looking at them W, no mod needed for that. We also can see mobs health bars.
Why do we need xp orb info?
Information about blocks might be helpful for people new to MC in general.
I've read "What Mod Can" seriously, all this we already do have available, is common sense and/or we'd disable it.