Completed the 3 temples. Here are my insights:
Combat. Ooof that one is a hard one! With no tooltips and only gut to follow through I got enough insight to see that "default items are not consumed, others maybe consumed, but sometimes don't" and "bottom lenses - one to heal and another is to deal damage". But there are so much STUFF. I see some heal/damage for more. And I don't know how to distinquish any of it.
I was mostly running away from mobs, collecting materials and engaging boss only. This is partly due to how hard it is to engage. They will only attack you if you are directly on their path and they move... so that was a lot of time needed trying to fight them and I am not sure if they got any loot in them or anything. Run and collect tactic worked like a charm anyhow...
I would love better explanation of combat system, more agressive mobs and... more missions to fly to :)