Hey folks.
I've been recently watching some posts about people who don't know what to think about a 6 skills bar because they have never played with that before.
My suggestion is: go try Guild Wars 1, the original.
It's not an MMO since it does not have an open world, everything is instanced but it will give you a better idea of what we will get about skills bars. In that game, you had 8 skills to choose from a huge pool and you had resources (mana, adrenaline, etc). It lacks some features of modern games of course, features like dodge/blocks, switching bars.... but it will still give you a better idea of what you will have on TESO.
I like to think about this system in this way: for those familiar with Magic The Gathering card game it's just the same more or less, you choose a fixed number of skills from a huge pool (cards in MTG) taking in account your resources (land cards in MTG) and making a good build (deck in MTG). So, if you are good making those builds, you can have a nice wombo-combo build, or a traditional build that works fine too, or a crappy build which don't server for nothing.
I hope you get a better idea about this system ^^
PS: Sorry about my English, it's not my natural language and I'm still improving it