I usually travel by myself w/my 3 girls (now 8,9,&11). We've tried the across the hall option and the suite option...but neither was as much room or fun as the connecting balcony rooms. With the connecting balcony rooms on RCL...not sure about other lines....the room steward (if asked) will open the sliding glass door between balconies....what a wonderful space to hang out on. We once had three rooms (family came along) and that balcony (with two sliders open) was heaven!
The connecting rooms are wonderful, especially when it's bed time....in the suite the adults had to "keep it quiet" and found it difficult to hang out...with the connecting rooms just close the door and poof "privacy" and "quiet" for the kids....we could still come and go and not disturb them.
I hated the across the hall set up. I felt so "disconnected" from the kids...and I didn't sleep good...felt like they were tooo alone. I couldn't go check on them without waking them (that door is so loud)...with the connecting staterooms the interior door is so much more quiet.
This is just my experience....as far as price....surprisingly I found the two rooms actually less then the suite on all of the cruises. I always price out all options and am surprised to find the two balconies less....I still never understand why.