i can only speak for my self, i started 24 generations and 34 1/2 levels ago to go more and more to agi, because i died constantly to 2h and polearm spam or backbeddal spam. Athletics and also a bit more WPM as full concentration on sound and footwork did solve that problem for me.
I have to agree with Kinn, despite that I hate his pick with a passion I usually reserve for the ladies. Many players here are hurting you, as a new player, by suggesting builds with 15 AGI. As a new player, with a shield (shields are very heavy and slow you a lot), you are making the game so hard for yourself with such low agility. I would sugest 15/21:
5 PS
7 shield, athletics and WM.
This will give you 150 wpf in 1handed, and another almost 90 to chuck into polearms, or throwing, or crossbows, to have a little bit of anticav/range abilities, and you can chuck your skillpoints left over into PT, or riding, or IF.
This may not be the most hardhitting build, but there is NO point in being able to kill enemies in 1hit if you never even get to hit them. This is a support role mostly untill you are a more experienced player, take some hits on your shield while you manouver enemies into a bad place so your teammates can destroy them with 2handers and poleaxes. with 7 shield you can catch a fair few arows before your shield gives out aswell, letting you rush the shooter, or keep a teammate safe while he reloads a crossbow.
REMEMBER: This game only shows Kills, and Deaths, but your teammates and yourself will know when you have helped them get a win, and they WILL apreciate you saving them from arrows, landing blows on enemies backs, and leaping over horsemen who have fallen, saving them from certain death while they lie on the ground mourning their horsey.