I personally couldn't care less either way, however having said that, I believe that the way it is is probably the best way to have it, and to keep it. On limited formal nights, ie: two during a seven night cruise, those who wish to go formal can do so, and those who break the rules, or wish to eat at the buffet can do their thing also. It doesn't bother me a bit if some folks are around the ship in casual clothing on formal night. They're comfortable, having a good time, and not bothering me at all, and those in tuxedo's are also having a good time, and not bothering me at all. Bottom line,,,does it really matter??
To answer the question at hand, would I book a cruise that's formal every night? If it's sailing to some ports that I really wanted to see,,,yes,,,otherwise probably not.