I'll try....

Life:    Healing, raising dead, holy/unholy
Fire:   Burning, heat, chaos
Water:  soothing, flooding, mystery
Earth:  mountains, defense, resources, land movement
Wind:  Tornados, Movement, communication, speed

Life – Fire:   holy flames,  hell hounds
Life – Water:   fish, poison, mass healing, purification
Life – Earth:  Plant growth/death, creatures of the earth
Life – Wind:  birds, fortune, luck.  (‘just cause' would be a MoM spell here)
Fire – Water:  burning hail, oils and liquid flame, acid
Fire – Earth:   Magma, volcanoes, burning rocks
Fire – Wind:  Lightning, energy, vigor
Water – Earth:  Mud, petrifaction
Water – Wind:  Ice, freezing, hurricanes, slowing down
Earth – Wind:   falling rocks, sand storms, sound (sonic burst and noise tremors)

I imagine that the most summons would be found under life.   If not (because life has so much to work for it) then I would say earth and water would be the two summon heavy domains.  So like fire-water would get mutants and strang crazy stuff.   Earth wind having some of the more magestic things like phantam beasts and harpies, and gorgons... what have you.

ah yes.  Earth-water definatly should have swampy things.    Maybe we should start also considering 3, 4, or even 5 element spells.

life - fire - water - earth - wind  :  void spells, prismatic spray,    Master of Magic/Cataclysm/ F-everybody-but-me-spells

fire - earht - water - wind:  nature rending, worldly mastery (like perfect movement through all types of terrain and accross planes)

Life-fire-earth :   Magma men, super buffs,  Chaos (if fire didn't already have it)

life - wind - earth:  Mass death, super mutations, sonic elemental   (If I used bleeba's dragon idea, it would go here)

life - water - earth:  petrification could be

life - earth - water:  Even better farm production, super swamp things

water - earth - fire :  wind-void, provides counters for many wind spells

fire - earth - wind:  Armagedon (this could I guess be all 4 elements as well)

multi-element spells is hard to consieve actually.

I think that void should be a combo of spells. Like if you are the guy that takes 2 books in every element (rather than 10 in 1 element) then you open up the void spells.  If you study every element, then naturally you'd know spells that would the absense of every element.

earth+fire+wind+water+life (heart) = void spells

that is what I say anyway.

I cast necro thread using the elements of troll and bees and bears

incidently I believe that all spells will be made using the shards mentioned in the lore section

The recent update on magic suggest there will be combinations of them and that they give out mana?