I haven't had time to read through the entire class, but one thing that I immediately reacted to is the alignment restriction. Not only is the alignment restriction on classes, in my opinion, a pointless rule which makes 3.5 less fun, there are numerous examples of chaotic mercenaries in literature and real life, making the restriction seem a bit arbitrary.

It is not hard to imagine a chaotic good mercenary, who strongly abides by his own set of morals while ignoring the common law, which is pretty much the definition of both the chaotic good alignment in the phb IIRC and the 'anti-hero' template we see in a lot of fiction.

There's also the chaotic neutral 'I'm only in it for the money, so I'll switch sides if you pay me more' mercenary and the chaotic evil 'I'll follow your commands as long as you don't show me where your money's hidden, at which point I'll stab you in the back and steal it.'