Eh. It depends a little bit on what level you expect to play this guy to--at low level I'd take Augury, but later on I'd want Divination or Commune (as soon as I could cast it).
Other amazing spells include Conjure Animals, Hex, Blessing, Death Ward, Aura of Vitality, and Sanctuary.
Since you're a diviner, I'd probably go with:
1. Augury
2. Commune
3. Blessing
4. Conjure Animals
5. Aura of Vitality
6. Sanctuary
The utility of most of these is obvious, but a quick comment on Sanctuary: it's a bonus action spell, compatible with Dodging or Blade Ward, and allows you to choose your battles and only get involved in important ones. It's a great spell for mysterious wizards.
I'd be sorely tempted to make room somehow for Death Ward because Contingency: Death Ward (whenever I am injured) is amazing.
Conjure Animals should be "Check with your DM".
I certainly wouldn't let my player dictate what kind of creatures they summon - the "DM has the creatures statistics" could imply that the DM choses the creatures. It might not as well, but I certainly wouldn't let a character summon 8 pixies.
I will pick the creatures that are summoned based on where they are and what purpose the character wants from the spell. Maybe they get 8 younger pixies that don't have polymorph and/or invisibility - after all I have their statistics.