I initially thought 1CANN to 1GRAM might be thinking a little too big but then I recalled something I read about CANN standing on its own independent of Bitcoin. That may be a bit off into the future but I think that possibility is very real.

I would also agree with solid12345 and coinpirate. 1CANN to 1GRAM will be easiest for the actual consumers to remember and once you set it you're kinda stuck with it. If it was only used to buy CANNdy, then as the manufacturer you could easily manipulate the rate at will by adjusting the cost of the product being sold to merchants. The moment other goods are able to be purchased with CANN, the ability to change the rate becomes nearly impossible, especially as widespread use grows.

In terms of mining and profitability, I just don't see that as too much of an issue really. The mining difficulty will adjust according to the value of the coin, as we all have seen recently, and if you were getting 100CANN/day before you might only get 1CANN/day after.

In the end, I think you have to do what's best for the consumers. Both the markets and mining difficulty will adjust accordingly based on what you decide.

That's just my 0.02CANN