OK, so I am back from my Pacific Explorer cruise.
All the wines by the glass are between $11 and 13. In general, they are quite good. Bottles go from a bit under 40 to over a hundred (including some celebration type stuff). As a wine snob, I thought the wine list was well chosen - solid and drinkable. There's a High Country sangiovese and a chianti for $40 which is what my local restaurant charges. If you want to splurge, there are plenty of good options well under a hundred. Be aware the lists change between the restaurants, the Italian varietals are all in Angelos.
The cocktails list is pretty much everything for $15. A couple of stronger cocktails hit 17 and so wouldn't be covered by the premium package, there's also an Archie Rose bar that does cocktails in the 16-21 range. These were the best drinks we had on the ship, AR is a good brand.
I never bought any soft drinks or coffee so can't comment. There is free mediocre orange and apple juice at breakfast, and just water at lunch/ dinner (no iced tea unlike other lines).