My favorite coin to buy is Bitcoin. Besides it, I believe in XRP and Stellar which have been growing by the market capitalization even during the downtrend. Also, IOTA can soon get into the top 10 due to dealing with the IoT market.
2018 has not been that good year for bitcoins and ether along with all other major cryptocurrencies. But rather to stay in them for long time, i would prefer investing in proportion in bitcoins as well as etherum. If we see the price for etherum now, it is comparitively much low and we can easily purchase and hold for a long time untill the price reaches moon. I heard about many different good ICOs lately. And I heard these are very good overally and it can be very profitable to invest in them but no matter what's the name of project one should analyze it deeply by itself before investing in it. I hope it will be useful for you https://www.hypeanalysis.com/blog/s...tform-approved-by-the-government-for-the-uae/
I really don't understand cryptocurrency to be honest, nothing really backing them, the behind the scenes of some of the companies is murky to say the least (especially bitcoin) which they use to then manipulate the value of the coin. If i were to invest in any (which I have thought about doing a few times) I would literally speculate with a small amount of money on some of the lesser value coins on the off chance that they make a move.