Both of these are unsustainable propositions. These are just manipulation strategies at best, especially the buying coins method. Yes, the first method could raise the hashrate which would lead to shorter blocktimes which would resolve this current crisis temporarily, but how long do you think you can ask people to mine at a loss before it is unsustainable?
The second method is completely impossible. If the hash rate is very low still and you attempt to place a huge buy order to raise the prices people will flood to sell. That buy wall will be vaporized before miners even realize it has become profitable to mine again. Whoever ultimately did that will be bagholding a huge amount of CAT which will almost immediately drop back down again and the hash rate will not get better.
The ONLY way to fix this is to fix the difficulty retarget settings itself.
I'd be fine with a fork to fix the retargeting issue, but I'm mostly suggesting to people supporting the Bitcoin-in-scrypt idea. If you like the idea, support it by investing in it. Either with hash, or by buying to raise the profitability. You would not need a huge buy order, just bump the price in the right direction. Pump-and-dumpers do it all the time, so don't tell me that it's impossible.