I personally think that Litecoin is a great long term investment. Especially, during the last months you could observe that Litecoin makes good progress and it is more and more decoupling from Bitcoins price (which is a very good sign that it becomes and independent crypto concurrency!). I have done some minging (several years ago), however, I stopped, and now I am only buying and hold. I think it is the easier and more secure way to get your coins. For mining you would have to buy special hardware to make some profit, which is expensive, hard to get, and error-prone.
I like to buy from https://anycoindirect.eu. It is easy, fast and secure. I have done more than 20 buys/sells already there.