4. Considering current Litecoin hashrate is 90 gh/s and Dogecoin is at 25 gh/s, it's currently at 28% of its hashrate.

also, litecoin has dropped in difficulty twice this week, down from 31xx to 28xx.
litecoin is dying, not doge.
to be fair, LTC had it coming.
hashpower and difficulty spiked when LTC went to $50, but ever since then it had lows of $10-12 and hashrate didn't drop (meaning nobody moved to more profitable coins and kept losing money on LTC). DOGE simpy helped correct both hashpower and difficulty for LTC, putting it more in line with its real market value, and nowadays more people is aware of the fact that LTC is not the most profitable alt coin anymore so they mine other alts for better profit.
Be aware that now that diff dropped considerably (about 10%) and prices are back up ($22.6 as per coinmarketcap), miners are returning to LTC as you can see in the following graph:
http://bitcoinwisdom.com/litecoin/difficulty, and difficulty will return to 32xx in a day or two.