if you go 21 strenght and 15 agility, you would have 7 powestrike, and as 1h, the extra 2 ps is way more usefull then 2 extra athletics, so my reccomendation is if you gonna stick with 15 strenght build, i suggest using some pierce or blunt wepons, though id go
Level 30 (4 420 577 xp)
Strength: 21
Agility: 15
Hit points: 60
Skills to attributes: 2
Ironflesh: 2
Power Strike: 7
Shield: 5
Athletics: 5
Riding: 0
Horse Archery: 0
Power Draw: 0
Power Throw: 5
Weapon Master: 5
One Handed: 127
Two Handed: 1
Polearm: 1
Archery: 1
Crossbow: 1
Throwing: 90