What the OP asked was a token, and I think GRIN is a coin not a token because GRIN already has its own network.
But there is nothing wrong with investing in GRIN, because GRIn is a coin that has potential in the future, many analysts say that the GRIN price will be pumped to 10 usd.

There are only two ways to make gas costs cheap, first you have to monitor the cost of ETH gas at any time, because there is a situation when gas costs suddenly become cheaper, and when that happens you can make transactions.
and secondly you only need to hold a token from the TRON network, because the TRON network transaction fees are very cheap. Even in the case of USDT the transaction fee is 0.

Hard fork coins are not a bad choice in my opinion, like Bitcoin cash, so far the development of bitcoin cash is very good, and every year there is always a network upgrade, but indeed during the last two years there were many conflicts that caused the price to fall.

Of course 1 GPU will not be strong, you have to have more capital than that to mine BTG, because BTG is one of the old coins which is quite expensive, so the level of difficulty is also quite high.
If you want to mine BTG, my advice is better wait for BTG to move to PoS, because a lot of coins are now moving to PoS, I didn't hear BTG is moving to PoS, but you can start talking to DEV and consider the idea.

It is a problem that has not been resolved since the past, many new projects have ended up scams and many investors have become victims, and they complain why there is no supervisor for the new project?
and in my opinion, this is not a matter of new projects to watch out for, but about how they don't get into the abyss several times,
those who have been deceived should learn not to be deceived again, this is the solution they must find if they are to make a profit.

I also have the same opinion as you, I see Dogecoin is only temporary hype played by the whales.
If anyone wants to invest in Dogecoin, my advice is to buy only 10% of the total portfolio you have. Because if more than 10% it is feared that the Dogecoin is not pumped by the whales again and you will lose very long, while the bull market has started.

Yes, it was not the first project that ended in a scam and discouraged investors. But OP has made the right decision because he sold all the coins he owned and bought ETH, now he only has to wait for the ETH price to go up to 10k usd,,

Cardano and Polkadot have no doubt, the ecosystem has been formed, especially Polkadot, I am surprised that the price development is so fast, there is a possibility that the market capitalization of Polkadot will beat USDT and ETH.
But after all Polkadot is only one coin, there are still lots of good coins, like XCASH which are still cheap and many people predict it will beat XRP.

Your Stop Loss (SL) target is very large, if your SL target is large then your TP must be bigger, at least 5x the risk you get,,
this is risk management, the greater the loss you can get, the greater the profit.
If I will at least take a profit when the profit has reached 100% to 200%, but depending on chart conditions and market sentiment at that time, such as a doge that has risen to 700% in less than 1 week

Mining is not profitable for small investors, because mining is only profitable when you have large capital.
so for those who have small capital it is better to choose staking, so you have nothing to lose even if you get a small prize, because you still hold the coin.

ADA and TRX can be options, especially TRX, which is currently ranked below market capitalization, if you look at the market capitalization of investors who are not holding TRX, it means that it is just a matter of waiting for the TRX price to be pumped because many investors will buy TRX.
for ADA, the price is actually quite high, but if you look at the maximum supply and price today, there is still a possibility that the ADA price will rise higher.

Litecoin and Dogecoin are coins that have good potential, I have them too, but I sold Dogecoin a few days ago when it was pumping 0.07 USD, now I'm waiting for Dogecoin to come back to 0.02 USD, so I can have more Dogecoin.
But do you also hold BCH? because in my opinion BCH is still cheap now and includes old coins which have good potential in the future.

There have been many Ripple issues since 2017, and at that time investing in Ripple was already risky, and now Ripple has a problem with the SEC, so are these issues still lacking to make us understand the risks of holding Ripple?
A coin that has many issues means that it has a lot of problems and risks. If there are still many coins that have no issues or even a few issues, why should we choose coins that have too many issues?

I agree, trading or investing are both profitable, depending on ourselves, discipline is very necessary to succeed in trading, knowledge and management are the first assets that we must understand in order to be disciplined.
And for investment it is suitable for those who are difficult to discipline, so they only need to hold it and wait until the price goes up.

We will not be able to eliminate the scam project, naturally it will always be everywhere, like grass growing in the fields even though the farmers don't want it, just like a scam project that will always appear among legit projects.
As an investor, it's better if you invest in coins that have a top 100 CMC rating, coins that have high liquidity are very good because their prices tend to go up.

It's easy if we calculate like that, but in practice it is very difficult to do, because what we do today is based on events that haven't happened yet, and we don't know what will happen, while the analysis you do is based on events that have already happened, the same as people who sell Bitcoin for 4000 USD, they do not know if at that time the price of bitcoin will reach 40000 USD.
Invest or trade depending on the time you have, if you have a lot of trading time it is certainly better.

If I can give advice, then I prefer ethereum, because ethereum is still very low in price based on bitcoin pairs, if I'm not mistaken now the price is still 0.03 bitcoin, and the selling target could be around 0.1 bitcoin per ethereum, because ethereum's highest price is around 0.15 bitcoin.

What is the minimum amount of DIA that must be held? i didn't hear the news, 60 usd is a hefty nominal since it's free.
I have never traded on the hoo exchange, but on Binance once in a while, I wonder why this airdrop is not so much talked about,

It is difficult to find reliable stable coins, but at least looking for stable coins other than USDT is the right choice, I prefer DAI even though the price rarely fluctuates, but it is safer than having my balance frozen.
The price of XRP will be very bad if the SEC issue is not resolved, I hope other coins like USDT have no problems with the SEC.

I'm not sure the news was made by the Ripple team, I don't even see the news as big news, it's just ordinary news that happens to be a lot of people sharing to many groups and think it's good news.
Cryptocurrency is very sensitive to news, even news that is not important can sometimes make the price of a coin go up, such as news about Elon Musk writing Bitcoin on his twitter account.