The Enchantress is a powerful magic user, and one that will need to keep enemies at bay. Here you'll be trading off defence points that other classes enjoy, in exchange for devastating spells.
This does mean that playing solo may be more difficult against higher-level foes, and as such, this class is best used as a secondary in a well-rounded team. If you're playing with friends, the Enchantress is a very strong pick.
The Warlord tosses around a massive hammer, and deals huge damage. With heavy armor and heavy weapons you won't feel unprepared when playing solo with this character.
If there's a complaint to be made, it's the speed of such a character. Again, you won't feel the strain early on while playing V4, but the Warlord might not prove as optimised as other classes in the long run.
The Slayer is a lot like the Warlord, with more of an emphasis on speed and attack. With the Slayer you'll be be inflicting status debuffs to your foes before landing huge critical attacks, meaning the longer the Slayer fights, the more damage they'll be dealing out.
This is another solid pick for solo play, or even for teams. The Slayer might not be as immediately user-friendly as some other classes, but anyone willing to learn will find the Slayer a great option.
The Knight class builds up strength and abilities as a fight drags on - similar to the Slayer you'll find this class to improve as battles go on, but unlike the Slayer the Knight is more honest, all about tanking hits and dealing them back.
Like the Slayer, this is another solid solo pick, and possibly the most immediately user-friendly of all the initial starting classes. If you want an easy introduction to the world of V4, then the Knight is a great way to go.
The Gunslinger is a lot like the Slayer class, able to deal out debuffs and slam opponents with critical strikes, but unlike the Slayer, the Gunslinger does all of this at a distance. As with all long-range characters, finding yourself against multiple foes can cause big issues, so playing solo might be difficult. Otherwise…
The Gunslinger is one of the most original classes and looks incredibly stylish. While this class might work better as a back-up DPS, the Gunslinger is so cool that it might be worth the risk.
Ah yes, the loli character. This truly is a Nexon MMO. The Boomblade reminds me of a Monster Hunter character, and you can expect some of the Boomblade's attacks to come out slowly, and deal ridiculously huge damage.
You'll be stunning enemies with devastating blasts, and generally tearing your enemies apart. This a solid, unique choice, and might offer you the most unique possible gameplay experience if you're coming fresh off of other MMOs.