Which altcoins do you think will be equal in price 1:1 with Bitcoin in 2-5 years time?

i.e.

1 altcoin = 1 Bitcoin

In other words, Mark Cuban would not buy into Bitcoin, but would buy into the 2.0 version of Bitcoin, an altcoin. Which altcoin would he buy?

If not match Bitcoin 1:1, what will be the new "silver" to Bitcoin in 2-5 years? Second highest market cap, after BTC?