Oh poor OP with literally no idea how crypto economy works.
But i have to admit that it was amusing to read.
Quote my words for future. Litecoin will hit 50 $ within a year or in worst case 2 years.
This.
Litecoin is being secured by its own ASIC hardware.
It will be the 2nd most secure coin on the planet.
Limit this mostly to CPU, so only full blown computers can compute it, and one doesn't have to buy special purpose hardware. The hardware will be useless otherwise and after all coins have been mined (unless the incentive to mine is still up and maintained in some way like unlimited coins or high transaction fee), the miner will actually throw it away or sell it to someone else (who may be a cracker who's accumulating firepower for bad mining). This is partially true for GPU hardware, but they have a gaming purpose apart from computational purpose, and probably the miners will themselves use it in gaming. So all in all, prefer 1) CPU only, 2) CPU & GPU, 3) Special purpose hardware.
With new hardware, mining efficiency will increase; the new miners of the new hardware will start accepting transactions of lower transaction fees making the old hardware redundant cause they take more electricity. They will be sold cheap cause of this reason (lower profit margins or even losses).
For an attacker, electricity cost is not of a concern, cause the attack time will be limited; he's going to earn money by making false transactions in blocks he mined.
Yes -- the old hardware is old generation, but that doesn't mean it'll be slower.
New hardware will not focus on higher hash rate, but power consumed per hash rate, thus, hash rate of new hardware may not increase exponentially making the network more vulnerable to attacks with older hardware.
I'm not sure about the architecture of ASIC miners to comment on that. It's not an ARM processor which can be made faster by simply by increasing the clock speed. Modern AMD and Intel processors are not 4xPentium/athlon 64 @6GHZ. So an improvement in architecture does not necessarily mean faster speeds, it may have been done to reduce electricity consumption by half. Look at mobile processors for instance; they are more efficient than their Desktop (per Whetstone and dhrystone score) counterpart but slower.
We just may have a similar trend for ASIC miners. Same consumption in electricity@little less hashing power.
This's still worst for small alternative cryptocurrency using the same hashing algorithm. They're easy to exploit cause of low difficulty.