2. "Faster" blocks: Faster but less secure. It's not the speed of the blocks, it's the *time* taken. 24 Litecoin confirmations are needed for the same security of 6 confirmations
That is totally and utterly incorrect.
6 Litecoin confirmations are approximately as secure as 6 Bitcoin ones. The amount of time taken has little impact
Suppose I made a payment 600 blocks ago and I want to double-spend it now. On the Bitcoin blockchain that represents about 100 hours' worth of mining I have to redo. Suppose (to make the math easier) that litecoin has blocks which are 10 times faster. Then that's only 10 hours' worth of mining.
I have access to a very powerful botnet. It has 10 times the hashrate of the whole Bitcoin network. I can rent it by the hour.
To double-spend my Bitcoin payment which has 100 confirmations I'll need to rent the botnet for a little over 10 hours. (10 hours to remine the 100 blocks, and a bit more to catch up with the blocks which were mined while I was doing that).
Assuming litecoin has the same total hashrate as bitcoin, I only need to rent the botnet for a little over 1 hour to double-spend my transaction.
That makes a litecoin transaction with 100 confirmations 10 times less "secure" than a bitcoin transaction with 100 confirmations (given the above assumptions).
Is there anything wrong with this argument? If so, where?