your pet choices to go with lofty libram will depend on how you plan to use it, AoE team or single target.
If you wish to have the libram as your main damage dealer, perhaps you can look at Celestial Blessing
The extra rounds you'd live for Arcane Blast
can really start hurting.
As 3rd pet I look at what your libram would be weak against, mechanical / dragonkin. Mr Bigglesworth, for example, being undead takes less daamge from Dragonkin abilities, and is able to deal ( a little bit) of Elemental damage, good for mechanical.
I assume you'd want want lightning storm. I would pick either Tiny Twister or Sunreaver micro sentry since both should be able to handle a mechanical pet, where your libram would probably not be able to take down fast enough.
The final pet in AoE teams should be a good single target one, preferably with a finishing move like Predatory Strike