Nothing too exciting here. Bladeforged 17 wizard / 3 paladin in draconic, magus and unyielding sentinel. Mass hold and meteor swarm are my two level 9 spells.
Just to clarify the build solos mid skulls and groups up for R10s. I am not soloing on R10s with this build.
Feydark Illusionist T5/Capstone focusing on illusion and enchantment with scion of the feywild. Uses force, fire and cold.
I use salt LGS in offhand but swap to shield against bosses when soloing. Against mobs use greater color spray, ring of shadowblades, meteor swarm, arcane tempest, ice storm to keep mobs salted. I try to time mass hold right, when soloing right before dragon breath. In R10s I usually just focus on keeping mobs salted and cc'd and by the time I am ready to use dragon breath the mobs are down.
For aoe I use ring of shadowblades (sometimes kiting if I have to when soloing), dragon breath, cold light of the moon, meteor swarm, arcane tempest
Trap the soul against low-will save enemies at range and finger of death against low-fort enemies at range.
I get rid of the arcane spell failure from adamantine plating with bladeforged, EK enhancements and filigree.
For single-target I have both greater ruin and arcane pulse buffed with draconic/magus on top of other wizard single target dps and the draconic dot. Since these buffs can't be turned off I go with force/fire/cold so I have a backup against things like iron golems (the greater ruin and arcane pulse buffs can't be turned off).
It's a high survivability cc/blaster build basically. Nothing ground-breaking, but I like high hp, prr, mrr, balanced dps (aoe and single target) builds for soloing.
In R10s with healers friend the cleric says I am reasonably easy to heal as I have healer's friend instead of repair amp in the bladeforged tree and some additional healing amp support.
I think this is a misconception - and a large one.
If the enemy makes their save damage is reduced to 50% in most cases. Then if they make their save and have evasion it's reduced to 100% in most cases where the save is a reflex save. So effectively it works the same way pathfinder and pen and paper works. There are a small # of useful spells with no save.
There is also damage reduction, immunities and sometimes spells flat-out misfire due to lag.
As far as ignoring everything except damage in caster builds, this is true in any high-end raid build whether caster, ranged or melee. In general when I build a caster for soloing it's very much a generalist with a high investment in survivability because casters are squishy without this.