It's a sad testament to the state of 1h/shield, but most shielders would agree that other shielders are their easiest opponents.
2h just hiltslash or backpedal or kick you to death, polearm will usually break your shield in 3 hits, maulers crush you, archers/xbow/throwers kite you, cav couch you. You have to significantly out-skill any of these classes to beat them. Meanwhile, a 2h or pole that's been playing for a month will usually beat a shielder of equal or slightly greater skill.
I've never played 2h in my life until I made a 18/21 STF mauler, and I do better with him just spamming overheads and never blocking than I do with +12 worth of looms as a shielder. Pathetic.