Help with difficult choice for 15th Magus level

I'm very torn for what to choose for one of the most important levels for the Magus, the campaign is loaded with spellcasters and we are about to face a lot them and specially a powerful Wizard King (maybe adapted/created epic level, yes our DM is very sadistic).

So I want to really really get the best out of my buck and I was thinging to get some stuff for my 15th I get a Magus Arcana and a Level Feat considering this is my final level, I dont know what to choose, here are some interesting options I'm considering:

1st Option
Magus Arcana = Spell Blending Enervation + Boneshatter/Calcific Touch
Spell Perfection = Enervation (for qualifying feats I have Piercing, Quickened, Persistant and Intensified)

2nd Option
Magus Arcana = Reflection
Spell Perfection = Dragons Breath (Quickened, Persistant, Intensififed or Piercing)

IMO 1st Option seems very interesting. And also I dont know what other spell to Spell Blend Enervation seems a perfect choice, other than that I dont know what other 4th level Spell is the right choice. So I need input please HELP!

Spell perfection for either of those spells seems like a bit of a wasted feat, it would be stronger with a spell you could constantly recast and preferably use with spell combat. Spell blending is good but if your at level 15 you have a decent number of spells coming up anyway.

What do you have at the moment feat/arcana wise, whats your characters focus?

Just a random example but vampiric touch is a strong spell for spell perfection, as is force punch to max out your damage die with intensified spell. Persistant spell seems like a bit of a waste but if you already have it its to late to change. Need to know more about your actual build to make worthwhile suggestions though.

He is a standard Devish Dancing Magus. Mainly using the Intensified Shocking Grasp Combo and some nice Mirror Images and Displacement for pseudotanking.

His main attacks are well placed hasted attacks using Spellstrike with the benefit of criting. Which he has on a 15-20 range with a +2 Icy Keen Scimitar he wields.

The Feats he has are: Combat Casting, Craft Wondrous Item, Dervish Dance, Intensified Spell, Persistent Spell, Piercing Spell, Quicken Spell, Weapon Finesse, Weapon Focus: Scimitar.

And the Arcana he has are Empowered Magic, Spell Shield (usually +5), Spell Blending: Resist Energy and Touch of Gracelessness and Critical Strike.

Vampiric Touch and Force Punch sound interesting, 2 Intensified Force Punches in a round mean 30d4 Plus Melee atack damage. With 25% Crit Chance (ouch).

And doing the same exercise with Vampiric Touch also looks promising I usually used Vampiric Touch as a last resort when healing was crippling. But 7d6 dmg that heal and that can crit sounds very annoying now that I come to review it with Spell Perfection.

My standard magus 15° level look like
Magus Arcana: Bane Blade
explanation: To me, is one of the strongest arcana out of there. 1 extra pool point for +2 hit +2d6+2 damage for 10 rond is devastating (N.B. it does not count toward you +x enchantment from your class)
Feat: Spell Perfection (Shocking Grasp)
explanation: If you picked up magical lineage for the shocking, maximizing and intensifing it for 60 damage is a 1° spell, you can chaincast them all day with a few 1° pearl of power (1k each, no reason to not carry at least 10 of them). And quickening them too, for extra attack.

I'd support the bane blade idea as it is an extremely good arcana, one of the few ways you can increase your damage with the dex build.

Spell perfecting something does seem like the best bet at levrl 15 when you meet yhe prereqs, i'd go for shocking grasp or force punch. If your already invested into shocking grasp and have the magical lineage trait go for that, pumping the damage is probably the best way to go but you really need another meta feat you can use all the time when quicken is no use.

You quicken one intensified shocking grasp, there is no need to persistant it as it has no save, if your not up against sr peircing is pointless so you have nothing to spell perfect onto it, you need dazing spell or maximised spell really as well so you have something to add cc to your non quickened spell, or you need to use quickened SG to deal damage with spell strike then spell combat a buff or control spell with your cast action, focusing on putting out two of your perfected spell in a round is probably the best way to use the feat though.

We are up against a lot of creature with Spell Resistant, Lamias, Dragons and other things we find SR difficult sometimes and taking that feat helped me a lot :)

Force Punch seems like a perfect choice to use it 15d4, that can Crit, Pushes and is quickened seems like quite bothering to boot! :)

I still think a Spell Perfected Blended Enervation can be stupidly crippling but not very on the character flavor. A the Ray Focused Magus on the other hand seems perfect for that though.

You know you can never go wrong with making sure you have Bladed dash or greater Bladed dash, then when you move into position, you still have your full round of attacks as long as you are using spell combat. REally nice for those casters who hide behind lines of people.