A faster first confirmation is an
enormous benefit if we want alternative currencies to be used in brick and mortar stores and restaurants. You can't have each person in line waiting 10 minutes or more.
You aren't going to have them wait 2.5 minutes (which may be up to 5x as long due to random nature block solutions) either.
So either payments will be prepaid, will be off blockchain. or the merchant will accept the low but non zero risk of double spend fraud.
When you consider the reduced security due to increased orphans and smaller overall network what exactly is the innovation. Now you may be right something "significantly" superior to Bitcoin may replace it but that significantly superior solution isn't LTC and the horde of copy cat pump and dump scamcoins don't even have enough momentum to break out of a paper bag.