So I have to modify things in multiple places?? I have to adjust the damage at every power selectively based on its other associated bonuses? ... might as well just have the implement act as a modifier... simpler and keeps it slightly distinct from the weapons and lets me keep approximately the current balance.
If you want wizards to get a little more oomph I think you need might need to address that more directly instead of forcing a rebalance calculation for every spell.
What I meant was lowering the damage of the implements by one step. But when I actually do it, it needs to stay within a certain range because clerics should do d8s and warlocks should do d10s and wizards should do 2d4 with the wand and orb should be d8 and the two two-handed items (staff and tome) should be above that. In fact I did lower them down one step in the below example. I don't favor the lowering though because it give little room to make superior implements.
Example Superior Implements
Forked Wand - as normal but 1d10 and +1 to attacks with thunder spells
Gnarled Staff - 2d6, Brutal 1
Bejeweled Staff - 1d12, +1 Proficiency
Correlon's Holy Symbol - 1d8, Proficiency +1
etc.
Implements
Improvised 1d4, one handed, Proficiency +0
Holy Symbol 1d8, no hands needed, Proficiency +0, Divine group
Orb 1d8, one handed, Proficiency +1, Arcane group
Pact Blade 1d8, off handed, Proficiency +1, counts as dagger weapon, Arcane group
Rod 1d10, off handed, Proficiency +0, counts as club weapon, Arcane group
Staff 1d12, two handed, Proficiency +0, counts as quarterstaff weapon, Arcane group
Tome 1d10, two handed, Proficiency +0, Arcane group
Wand 2d4, off handed, Proficiency +1, Arcane group