It could work, but it might be a bit tricky to keep your mana filled.
I'm running a mage/bard with 6x 120
mage
med
eval
prov
music
discord
It's working extremely well (especially on the invasion content). I can prov things together and then nail them with slayer meteor swarm and chain lightning.
I don't think spellweaving has enough flexibility built into it to be a stand alone skill. You will almost definitely need magery for the invis spell and probably the offensive spells. That means we're looking at an extremely tight template, so you have to work your way through what you can sacrifice and what you can't.
You can tweak the prov/disco/mage template to build a SW/mage/bard that's probably pretty powerful, but you'll be really tight on skill points and probably mana. You really only need to get magery up to 92 to be able to cast 6th circle without fizzle (which you really want to be able to do). You definitely want 120 music, discord and provoke. You probably want 120 eval, but also probably can't squeeze that onto your template.
You can cast 7th circle spells like meteor swarm and chain lightning from scrolls. They are extremely powerful spells on a template that has provoke. Basically, you prov 2 things together and then blast them both for flamestrike damage.
The consept behind playing a SW/Mage of any kind is to use the strongest spell in the SW arsenal. Arcane empowerment. If you have a lvl 6 focus, it will give you 60 bonus SDI. The only thing you sacrifice by having 100 SW instead of 120 SW is 1 second of duration.
Another spell in your arsenal that will be particularly relevant is wildfire. You have the ability to tie things up with provoke and then burn them down with wildfire. This spell is extremely powerful if you have a high lvl focus.
You definitely want to build a set of super slayer spellbooks. If you can, get super slayer scrapper's. It takes a long time to build a set of those (I don't know anyone that has one), but that collection is the pinnacle of power for any pvm caster.
I'm kinda thinking this through as I go and I'm thinking of all kinds of problems you'll face. I think you're looking at a template something like this
120 Music
120 Provoke
120 Discord
75 Magery (crystlaine ring takes you to 95)
100 Spellweaving
100 Eval
85 Med
you definitely want to wear crystaline ring and orny. You'll need the SDI and mana economy from crystaline ring. You'll probably need the casting you get from orny. If you can get by without the casting from the orny, consider wearing skill jewlery on your bracelet slot, so you can get more med on the template (or eval to just increase the dmg of your spells).
At 100 Spellweaving, you won't fizzle Wildfire, reaper form, attune weapon or gift of renewal. You'll have a 93% chance to succeed word of death and a 65% chance to succeed arcane empowerment (which will almost definitely annoy you). If you can get to 110 SW without killing your template you will have 85% chance on arcane empowerment and 100% on WoD.
You will absolutely want to have max LMC and as high of MR and SDI as you can reasonably fit on your suit.
If you use reaper form to buff your SDI, you can use teleport to escape some hairy situations. A lot of high end areas disable the teleport spell, though.
Well... that's about all I have for you. You'll be really pushing it to pull this template off unless you have some really hardcore items. Maybe imbuing will make it easier for you
