As you have said, I use ETH for these purposes:
For trading
To buy ICO
For long term investment
I keep the majority of my ETH in MEW. I won't touch it for a long time.

Maybe you are right that some airdrops are worth it.
For me, I don't participate in any kind of airdrop.
The reason is simple, I don't have that much time to find the good ones.

Ethereum is one of the most undervalued coins in the market.
It is widely used as a platform and more projects will be based on it.
I always take the  chance to accumulate more ETH.

SelfKey is one of the most undervalued project in the market.
It is good time to accumulate more of it now. Good time is waiting for you.

You should be very careful while choosing ICOs.
Some of the top ranked ICOs in icodrops or icobench turned to be failures.
You must do your own research.

ICO investors are faced with very limited information about the ICO.
It is really hard to tell whether it is a scam.
All we can do is checking the background of the team, read the whitepaper.

Selling now is not recommended. The price will pick up quickly.
If you wanna sell now and buy back with a lower price, you might find you can never do that.

It is common that coins are dumped below ICO price after distribution.
You should be very careful while choosing coins you are gonna to invest in.

I must admit that there are more scam bounties than legit ones in bitcointalk.
I don't know if we can do anything about it.
As far as I know, people investing in scams can't do anything at all.

Absolutely yes! Ethereum is one of the best blockchain project available.
Its core and source code is available on github and its free to use their kit for general purpose. Most ICOs  using it blockchain.
ETH is the most successful cryptocurrency so far.

Selfkey has been falling since its list in Binance. It must be manipulated by some whales who wanna accumulate more tokens before another pump.
I believe there will be a reverse very soon, given its solid team and continuous development.

The Plan is to hold strong and diversify the investments since it's a lot safer then being invested in just one thing. 
Learn to be even more patient and not fall for the fud or fall for the fomo.

You are not alone.
It seems to me that everyone who invested and invests their money faced such problems.
Patience solves everything, but sometimes it is not enough. Therefore, we still need practice. We all learn from our mistakes.

Patience is really the key. Most people in cryptocurrency don't have this virtue.
As they see their portfolios falling, they tend to panic and wants to sell them off to avoid losing more. They don't know that it was just temporary and the market will recover again.

If Ethereum was called scam, then most of the coins out there were scams for sure.
Ethereum is the most important infrastructure cryptocurrency so far. Lots of applications are based on it.

Off course yes. If I don't then I won't be investing time, effort and an ample amount of money into it.
Cryptocurrency is a good investment for people who knows how to be patient and know how to be keen on current info coming that can affect future of coins.

I don't think it will take up to that long to recover. 
I believe the market will recover before the end of the year.
The whales in charge of market manipulation want to get more money so waiting 2 years won't be acceptable to them.

Ethereum is one of the most powerful coins in the market. Ever since I entered the crypto stock market, I've been following Ethereum.
It will be valued more in the following periods. The advantage of having your own network.

The market is very versatile and sometimes you gain some and loss some.
Be patient and hold. Do nothing and sell when it reaches your stop loss or profit target.
We can't fully predict what will the market be for tomorrow. Just take this lost as a lesson and do better in your next trade.   

It is completely up to You. We never know bull run can start even from here and you might never see alts in current prices again and you going to miss the train.
But I always believe it is better to tether your portfolio when Others are fearful to do it.
If You happy with what you have got and not in any losses No danger in selling , But if You are in a loss it is always better to hodl.