I would eat more and work at building the back with heavy rows as an accessory. I also think a good squat transfers to deads very well. I also think pulling both sumo and conventional compliment each other.
Also how's your form? ie are you getting all the leverage possible?
My Favorite Part Of Lifting Is Having The Opportunity
Meet PR's: (May 2014) Raw Natural
Squat 475 lbs
Bench: 286 lbs
Deadlift: 501 lbs
Total: 1262 lbs
Squat: 495 lbs
Bench: 300 lbs
Deadlift: 520 lbs/500X5
Total: 1315 Lbs