Hi all -- these are two common questions coming up in the General Chat, and thought I'd take a minute to explain.
So for those who are just getting used to the ability wheel, many are asking if they can "respec" and choose different abilities on the wheel. Or if they should "re-roll a new toon." The answer is no to both questions, but read on for the reasons why:
In general, the reason no respec or re-roll is ever needed is that it's easy to look in the wrong place to do the "re-speccing." The ability wheel is simply the pool of abilities (525 of them!) that every character can draw on. All characters, as they progress, will eventually unlock the entire wheel (pool) of abilities -- nothing you buy on the ability wheel is ever wasted. Re-rolling simply puts you back at ground zero, and there's generally no need to ever do this unless you want to try a different faction. (This is also the reason there's only 3 slots for alts.) AP earnings come fast in the game (you can even re-run missions if you want to go back and farm a few more AP), so it's easy to pick up new abilities on the wheel for your pool.
But here's the real key: if you really want to "re-spec" or "fix your build" the place to look is not to the wheel, but in your equipped (7 Active and 7 Passive) abilities: the Deck.
If you've determined that you need to equip abilities that work better together, or are not being effective in combat, take a look at your equipped Actives and Passives. The key to an effective deck is finding Actives that work well with your Passives. All Active abilities can generate conditions (e.g. "Impaired"). These conditions can be exploited by your passives to create a powerful 1-2 punch, a combo.
When you are reviewing your deck, realize too that while your equipped Active abilities must match your equipped weapons, Passive abilities can be equipped from ANY weapon. This gives you a much larger pool of Passives to draw on for your deck, and also can result in some of the best builds in the game.
To make it even easier, there's a handy Search panel to the right of the wheel where you can look up conditions you'd like to exploit.
In summary, if you are having a problem with a build, most likely it's the abilities you've equipped that are causing the problem, not the pool of abilities you have available to draw upon.
With all that in mind, the way to respec is to "course correct" your deck. You can look at the starter decks in the panel to the left of the wheel and find one that's close to where you are and work towards it. Or you can use the deck recommendations in the forums and do the same. Finally, you can look through and research the abilities to find Passives that work with some of your better Actives and work towards getting those abilities; making your own build is the most fun, and is potentially the most powerful (you can also create sucky decks too, but that's the tradeoff of freedom). Remember that AP come fast and that no ability purchased on the wheel is wasted.
Eventually you will have multiple decks that serve different purposes (tank, dps, ranged, heal, aoe, single target, whatever). You'll start out with a single deck, but it will become necessary later in the game to be able to switch to different decks depending on the mob or situation. So start focused, then branch out. Think of the style/philosophy of play you want to work towards for a particular deck, then choose weapons and abilities that help you accomplish that goal.
For an excellent primer on the ability wheel, decks, weapons and combat, below are some recommended resources:
Also, check out the Builds and Decks forum:
Finally, you can also test out weapons and abilities in your faction's training facility. Any AP spent in the facility is not permanently used.
Feel free to ask more questions as they come up, and hope this helps!