We were on the Sun to Alaska in August. Our first cruise, so not an expert
I highly recommend the balcony room unless the extra expense is not in your budget. We found it very enjoyable.
Our final total of on-board expenses came to $1312.00. Included in that:
Shore excursions ($370)
Automatic Tipping$10.00 per person per day-($140)
35 minutes of Internet access for the week ($30.00)
USA Today ($19.75) (Surprise surprise...didn't know they charged for this very brief version printed from the internet and delivered to your room each morning)
Specialty restaurants ($56.00) (Le Bistro & il Adagio, both wonderful)
Gift shop ($180.00)
Casino-Slot tournaments, Bingo, etc. ($400) (won $300 at Bingo
Remainder was for wine and some extra tipping (which was optional) at LeBistro and il Adagio
Two other things we didn't know about. All alcoholic drinks have an automatic 15% tip added.
Also, if you drink wine, it is cheaper by the bottle and if you don't drink it all at one sitting, they give you a voucher, keep the bottle and will deliver it to wherever you happen to be when you want to finish it.
As you can see, we didn't spend much on shore excursions and 'booze', and maybe too much on gambling
All-in-all, we thoroughly enjoyed our first cruise on the Norwegian Sun.
Hope this helps and if you have any further questions, I'll try to answer them for you.