Or how about we keep spellcasting the way they have it now, and have enchanted weapons the way they were in Oblivion and Morrowind (cast on strike (yes I know some Morrowind weapons were cast when used, I'm not talking about them))?
Well because cast on strike require physical contact with target and cannot be invoked by hitting environment like OP describe, as well you cannot cast target enchants with melee weapons in Oblivion, only staffs capable to do thats but they are almost useless in close combat by ridicules reason we can parry with them all strikes without consequences since they are didn't have durability but cannot strike with them even if they looks like some heavy branch or stick or quarterstaff.
Staffs in Oblivion are fantasy energy guns thats all uses the same battery charges and even don't have of any requirements, now in Skyrim we can even akimbo such 'guns' for maximum damage I think thats make staves lose great portion of arcane mystery as magic tool and weapon.
Thats one of parts of bad enchanting implementation in Oblivion, fixing such flaw take many mods for me so in unlike of vanilla modoblivion much closer to previous games and feel more like actual TES game then another generic fantasy Action-RPG, so there is question why such work is done by modders while thats work of devs?
Enchanting must have returned cast on use enchants as well have separate way to cast enchantment spells from one enchanted item for example
Obsidian Staff of Blazing Fire MasteryCan shoot fireballs on swings and strikes when target at distance like oblivion staves and staves in modded morrowind.
Shooting uses charges, projective have different speed what can depend on quality of staff material (durability and cost) and magnitude of enchantment spell or charge usage, thats work well with enchanting limit thats depend on material and cost of base item.
But when target in close combat staff can be used as blunt weapon with all properties of such weapon (like apply of perks) different combat movies, speed, damage and durability and usable for parry, of course it will have unique model of Obsidian staff not broken wooden stick thats previously was used as toothpick for giant.
In close combat staff can do more damage then on target for one charge cost as well can apply fire damage overtime with each strike while such additional effect is chance based for on distant target shooting.
on equip such staff add fireball spell to mage spell book so mage (thats specialized in different then destruction school) can cast spell what he don't learned and don't have enough skills to do thats but have enough magicka to cast such spell difference in thats that staff shoot are not chargeable while spell is can be charged so mage swing with staff and shoot from it an fireball thats have fixed magnitude and uses charges and cast Fire Ball spell thats equipped in another hand and have chargeable magnitude thats depend only on reserves of magicka,
additionally such staff can increase skills of wielder in destruction magic school and temporally add an perk from it, when staff is unequipped bonuses will be removed as well as spell from mage skill book, additional there is can be also some interesting effects like improving fire resistance on equip in cost of ice weakness and fire damage on unequip or adding fire shield when parry to burn foes up all such effects can be constant (for expectational and artifact items) or be activated on use (for middle level and low levels ones)
All options of above can work separately as different enchant effects in one base item similar to different way of spellcasting with new magic system, but better if standard magic staves will combine at last two of them, while artifacts will have more variable ways of their usage as well can have some unique spell effects thats work only for them, like reanimation from Staff of Worms or Wabbajack from Wabbajack.
Additionally as magic tool for better concentration such staff can increase concentration checks (ability to cast spell without failure when interrupted by strikes or other disturbing effects based on skill levels in magic schools versus cost of spell so charged spells or powerful ones can be miscast with lucky strike watch your enemies and use tactic in combat)
and reduce penalty to spell effectiveness from wearing armors (with small enchant limits so spell effectiveness will depend on quality of armor but armor will always reduce it, both concentration checks and reducing of penalty to spell effectiveness as variables can be used in special traits, perks from special training in guilds)
In such cases Staff will really magical other characters can also use such weapons but until they have special training they will not feel all benefits while mages will have them, if someone think such features cannot be done thats is wrong because all such features was done previously by mods and involves simple scripting and even was available for Morrowind before.
If skyrim will have flawed Oblivion staffs
Then there will be again wooden boomstick thats shoot fireballs and uses soul gems as ammo thats have no difference in usage for skilled mage and barbarian who just take it as loot and receive all necessary arcane knowledge in one second, but now such sticks can be used in dual wield, what are powerful akimbo "gun" combination we will have, if we have such energy guns why all against of firearms thats uses gunpowder then?
I don't want to see such flaws from oblivion again but now multiplied by x2 from dual wielding, when better implementation is not hard to be done.
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Note to self: oh well thats was my one thousand post, I hope they all was were constructive and interesting for readers.