Bearing in mind that the only out-of-your-way thing that you have to do to earn these rewards is to move from PJ to LJ to get to the goblin, then gamble your points; I don't imagine that the actual rewards will vary too much from this. Imagine how pissed people would be if T4 VW drops were added as a possible reward! (even if the drop rate was as low as when you do VW itself). I imagine that rewards will consist of perhaps abyssea seals and +2 coins/stones etc. Maybe even throw in the occasional beastman/kindred seal, or crests.
Or perhaps just more augmented gear, similar to the battle trophy aug.gear in heroes areas.
The reward for speaking to an NPC (even if you are in a position to speak to it EVERY DAY FOR A YEAR, which most of us are not) aren't going to be amazing. I'd be happy with an item that NPCs for 5-10k for the amount of effort put in tbh.
If the system is implimented so that every consecutive time that you use it, your reward goes up, that's just wrong. People get penalised for taking a holiday? No thanks, not for me. If it just increases every time you use it, that's fine by me. People who remember to check it every day will get the better rewards sooner and that's fine. Though it would either have to reset itself after you get a big reward, or the top tier of reward would have to be not game-breaking. After 5 years, you get a relic/empy/mythic every day XD