FTTF came before offering it as a perk. It is a revenue driver (whoever thought of it should have got promoted). If they dropped it from a loyalty perk, it would continue as FTTF. When half the ship has it as a perk (from a loyalty persective), it simple cannot be done in the time constraints..
There are options, and I love the perks, just stating the reality of the situation. IMHO, the easiest way would be keep the same things (more or less) but cruisers wold have to aintain some level of persistency (like cruise X times within X period of time, or they drop off.