As was said, hoplite is support more than anything. You need a buddy who you will be runing around with and augment his attacks with your stabs. It is very effective if done well. If you find yourself alone against someone, your only chance is to put shield on your back and play classic polearm dude. I would suggest warspear, as it has no penalty with shield and overall is very good polearm.
But yeah, you really need to pick someone on your team and stick with him. If you're part of a clan, it would be easier to do some coordinated stuff which would make you shine.
I wouldn't say hoplite is not viable. It is, just very hard to pull off as it doesn't depend on you how well you will be doing.