I first bought ETH in July 2016 when price was around $10 / unit but I still believe that it is worth buying it now ($300).

More and more people are interested into cryptos either because blockchain is getting very popular (and no longer restricted to pure technology enthusiasts) or because they hear a lot about people making fortunes out of it. From a newcomer perspective, the key drawback of XTC is its current price ($4300) - quite deterrent if you want to invest only a few amount. You might double or triple your initial investment but you'll never get rich. So the newcomer (who wants to get rich within a few days) will look up at the current crypto ranking and he'll decide to invest in crypto number 2: ETH. Why? Cheaper than XTC, plenty of literature which is quite an advantage when you do not know anything about crypto (compare to XRP, LTC, NEO, NEM etc), big potential and quite well integrated. If newcomers decide to invest in ETH, it's good for the community and the price of ETH.

I recommend Lykke for the long term - they have published their 2016 Business Report if you want to read more about the project. Recent integration with Ethereum in June. Very promising in my opinion.

A lot has been said about XRP but I still believe this coin has much potential on the long term.

Not at all - just curious and very interested about the topic and any project that could be related to it. Please no unjustified accusation. Let the opportunity to newbies to express themselves thank you.

Are you aware of any current or upcoming blockchain project applied to healthcare / social security?

The intent being to facilitate the relationships between (i) patients, (ii) social security or private health insurance organisms and (iii) practitioners and pharmacists for health care payments.

For instance, any project intending to get rid of paper medical prescription?

Maybe you have heard of any altcoin which intends to support or reproduce the above.