Im looking at putting roughly 10% of savings into crypto... is that bad
I assumed that it would be more of your savings than that, since most teenagers don't have access to $10,000 of their own money. But 10% is fine and it could be an interesting experience for you, I suppose.
I don't like the idea of storing the coins in 'Coinbase' or 'blockchain.info' because I know they control the private keys and they could be hacked.
Blockchain.info doesn't have access to your private keys. But your concern about web wallets is understandable.
But is there ANY risk that the back end developers can access take my Coins ?
It's unlikely, but there is
some risk.
Im thinking 50% bitcoin, 25% lite coin, 25% ether ??
Knock yourself out. If you want more advice about that, head to the altcoin boards.