My wife and I are now both retired and we cruise more than 150 days a year, and to keep up that pace we always cruise in an inside cabin. Celebrity is the best in this department. Cabins are large and well designed, and we've never felt uncomfortable. We sleep so much better in an inside cabin because of the total darkness. We've cruised in multiple balcony, OV, and even a couple of suite cabins -- not worth the extra cash (IMHO).
If you are doing a "trip of a lifetime", sure try the best cabin you can afford, but if you are doing BtoBtoBtoB and that's just the start of the year, save some money and book a well situated inside cabin. After 930 days of cruising, the whole upscale cabin thing is lost on me. Example: BtoBtoB in Alaska in May (total for two people) = $3,816, all included for 21 nights on the Solstice, or a 7-night cruise in an S-1 Suite at $3,692 on the Solstice.
Enjoy!
Kel
PS -- we do like those forward facing OV cabins!