Lite means ANYONE can mine Litecoins - you don't need powerful GPU, don't need AMD GPU
You can use any CPU you have and mine coins efficiently!

Lite means system will have less hashpower than Bitcoin (because of CPU mining) - not an issue
Lite means faster confirmations of transactions what is really important for any market or shop
Lite means nobody premined coins for himself so we have fairly distributed coins

About supercomputer hostility: just give Litecoin time to grow. Neither Bitcoin was supercomputer hostile at the beginning.

About botnet: botnet issue is solved pretty easy - identify botnet and block IPs. Forever.