But Destiny offers a crap tonne more than Halo ever could in other areas. Much more variety of items, weapons, armors, abilities, skill trees, progression system, upgrades, reward factor, much larger environments and better visuals and art, more community aspects, more sociable mission design, overall more ambitious design, greater range of enemy diversity and types, challenges and bounties, more to collect and do, see etc.
You mention vehicular combat in all levels as a positive, that to me is a negative. I prefer the variable and more diverse nature in Destiny's balance. You talk about difficulty multipliers that make Halo more repayable, but Destiny to me is considerably more repayable, because not only do you have the different difficulties that grant you better loot, experience, drops etc, but in some missions you also get re worked gameplay with more enemies, new enemies, much higher rate of aggression and special enemies etc. If you're playing in a fireteam, the experience is usually even more variable due to the diversity in others people's weapons, tactics, classes etc.