Well Time could hold it's own meaning in various ways much like breath could mean either air, or literally one's breath. A Prince of Time could, more or less, destroy another's time; an assassin.
An Heir of Rage would be impervious to his own anger and could bring out the angers in other easily. A master of provoking while being immune to the same effect. The ultimate troll.
An Heir by definition is one who has complete dominion over something. Ie: John is the Heir of Breath and so he can completely manipulate wind. The Maid is the female version of this class. Light translates roughly as "something of fortune". This can be seen by how Vriska, The Thief of Light, 'steals fortune' by being able to alter luck-based outcomes. Again with Rose, The Seer of Light, who is able to 'see fortune'. By these examples a Knight of Light would be one who either 'Protects with Fortune' or 'Protects Fortune'. A class like this would play a very positive role in a session as he would be able to safeguard a game's progress, singlehandedly being able to keep the session from going null or void. Other things would be unlocked upon getting Tiger but that's up to you to think of.
This is awesome. We need a plot. A preset plot, we can't have any walk-ins with time shenanigans going on. To have poni trolls or not, that's the question.
Never read it, though I've been thinking about starting up a Homestuck RP in the RP section of the forums. It'd be difficult to make a decent plot for it though, so you should totally help ;D EPSTUCK