Greetings all, I've been noticing that my destruction spells have been costing a lot as of late (just got to adept level) and it seems as if I'm gonna need some kind of reduction to still efficiently use it. My character is a nord battlemage/spellsword. Specifically I'm planning on putting my perks all into Block, One-handed, Destruction, and Smithing.

The way I intend to play the game is to get to level 50, no more and no less, and then beat the final quest. After that point I will start a new character, repeat the same process.

Ive actually taken the time to fully plan out my chars (including this one) and I have every single perk accounted for in those four trees, no room for anything else. However now I'm at this whole problem of spells costing too much and the only suggestion I'm finding is to put perks in enchanting to reduce the cost of spells. So at this point I'm wondering, is there any other option other than that? Because it seems without the perks it would barely be of use.

You could just buy items with the reductions already on them. But you'd have to be already fairly high level to get good ones which is already your end game.

you will have to find or buy gear clothes/robes/jewelry with good perks already on them....Radiant Rainment has great gear....so doe's the mages college.
If you are going to wear light armor the you are toast...burnt toast....even with top notch enchanting you can only add weak perks to your armor....I had max enchant and the gear I could double enchant had at best 25% of the perks that You can get on robes/clothes/jewelry that you either find or buy.

The weak perks help, they just don't save you the magicka that you need to cast higher level spells.

I'm not sure I see reasoning of calling your character a battlemage when you don't want to put perks into any magic. Your perk selections seemed to be pure warrior

He did say he was putting perk points into Destruction....read it again. He wants the Offensive benifits of a mage and the Defensive benifits of a warrior.
Was good style to play in Morrowind and Oblivion but, A lot harder to do in Skyrim because of the Perk system.