you have a very unusual site, I liked it. I would add some bonuses (for example, a double Deposit) for new players

Double deposit = 100% deposit bonus, it is usually come with high wagering requirement and players are not really attracted with such bonus as far as I can see.
Better to offer something else than deposit bonus such as contest, competition, etc to attract all players.
From what I understand, those double-deposit bonuses are targeted to whales that will have higher chance of achieving the wagering requirement. Small time rollers will not even bother to avail it.

And I agree with you. They really need other advertisements to compete with other famous dice sites out there. They'll be climbing a very steep hill to overcome it.