I've been mixing around a bit on my healing setup as I now have hit level 12, and after some tinkering, it struck me that healing spells for sorcerer doesn't count towards the spellpower side of things.
So it turns out that weapon damage increases my healing done. So would it then be best to combine the Martial Knowledge 4 pieces (which after it's been fixed should grant 50 weapon damage) with the warlock set 3 piece, for magica regen and max throughput?
As far as I could deduce, my critical surge - which grants 56 weapon damage - increases the effectiveness of my healing spells by 15%. So combined it should give a very nice healing output.