For games that can fit on 8 GB carts or lower I am not willing to pay anymore and I do not appreciate companies using smaller carts than 8 GB if their game cannot fully fit on them. The reason I have this standard for the 8 GB carts is because apparently the retail packaging Nintendo sells for those costs the same as the standard retail software package on the other systems (btw this does not mean the carts cost the same as BD disks to produce, but rather just that Nintendo sells those retail packages as the same price as Sony and MS's standard packages).
For 16 GB and 32 GB games I am willing to pay an amount that covers the cost of the game, but I also do not mind devs choosing the 8 GB cart combined with a download.
As for your side questions:
2. Not sure. Most platform companies make a profit on the physical packages for their games, if that is the case for Nintendo I think they should break even for a while on the larger carts in order to reduce prices for publishers, which would spur them on to use the larger carts, which would result in higher manufacturing of those carts and hence a cost reduction over time.
3. Games that are at or below 8 GB should always fit on the cart without any downloadable component, as the 8 GB cart retail package apparently costs the same as the standard physical release package by Sony and MS.