And what aura for higher lvls ?

Redemption for solo play. Play whatever is fun!

Depending if you with a team or solo I think changes it.

As Papasmurfs said Redemption is a great option and 1 I normally put 1 point into to help with mana consumption.

Salvation I normally run in a group to help keep my teammates res up (mostly for hardcore mode)

Conviction also good for increased damage on FOH and your teams elemental damage if you playing with one.

You could do Mediation while putting points into prayer and cleanse.

conviction if party play - ur teamm8s will thank you

for lvl 30-40 use resist cold