Rellana was a good boss, got her sub 30 attempts but it was enjoyable to learn unlike the spastic lion. Golden hippo was too big for it's arena, something from soft are still doing and they must know it becomes junky. Easy though I'd have beat him first try had it not been for the camera, went down in the fourth. It's the standard enemies that are the problem, why are there so many mini bosses disguised as standard mobs, it's not fun, the messmer dudes in shadow keep are the worst yet. I'm a bit afraid of messmer from what I've seen so I think I'm gonna detour from here and see if I can level up my scadutree.

Those bastards clad in red and dual-wielding curved blades are the worst, the whole keep is full of them. A lot of enemies have some real BS-length combos in tight quarters areas, and they often roam around in areas with a bunch of other mobs as well. Damn, I need a break! Attempted Messmer a few times, but grew tired. Phase 1 isn't so bad, his attacks are mostly easy to dodge, especially when you roll into him instead of away from.

You can only get two Uchigatanas in NG if you started as Samurai. The Uchigatana is a catacomb in Northern Limgrave

Occult Infusion makes your weapon getting scaling with Arcane and increase stats buildup such as bleeding and poison. There are few Ashes of war with occult scaling. The best way to give a weapon occult affinity is using the black whetblade, you can find it in Nokron

It's worse than bleeding infusion when it comes to proccing bleed, but it's add strong arcane scaling so thr damage output is high without compromising your ability to make bosses bleed 

At 80 ARC it's only marginally weaker than Keen Uchigatana with 80 DEX, but with much higher bleed buildup: 

11STR 15DEX **80ARC**:  

Occult Uchigatana = 585AR / 88 Bleed  

11STR **80DEX** 8ARC:    

Keen Uchigatana = 596AR / 45 Bleed

Combined this with Mimic tear and most bosses will bleed in every combo

However be aware some bosses are immune to bleeding, many of them actually. If you don't have many Larval Tears you can go for DEX and change the affinity to Lightning, Keen and Blood Infusions whenever you see fit 

If you really to keep INT and be a magic Samurai I strongly advice to use ranged magic and abuse Moonveil's Ashes of War. Intelligence builds are great, but a good spell blade build is about mid-range fights (using Cold, Ashes of war and some ranged sorceries) and your playstyle looked 100% meele for me 

If you want to meele IMO DEX, ARC and STR are better stats than INT

BTW, what build are you running for the DLC? 

I will start playing DLC tomorrow. Have been on vacation for the last few days. Until undecided on which character move to DLC, most of my characters are NG+1 and NG+2, I think only two are still on NG

Strength builds are doing best from what I've seen and if you don't mind using a Sheild, there's one that trivialises the game. You're going to be doing a LOT of rolling if not so remember the 50 END that you told me is too high is not tbh. Best of luck, hope you choose wisely.