there have already been a couple of altcoins that had a price higher than 1 bitcoin. i can only remember 1 at the moment called ZCash which started at 6-7 BTC price (1 ZEC = 7 BTC) but none of them last ever. now ZEC is 0.07BTC and falling. because the only thing that can keep their prices up is the demand and since they have no real demand they always fall when speculators (the only demand they have) exit.

to answer your main question, any coin that is invented in the future to perform as a currency not as a way to get rich of with premine and ICO, and also solves a couple of problems can become bigger than bitcoin and have higher prices. but that coin is not yet invented.