Always better to plan and make a good mindset, diverting your assets always bring good things whenever you have good knowledge bad understanding, stop chasing something that still speculative but rather focus from something which is already been offered, always make right assumptions and be ready to add patience.

I agree in terms of there will not be a 'next Bitcoin'. This is a bit of a marketing gimmick used to lure in newbies. It's sad because a lot of the newbies seem to be those looking for a 'get rich quick' Cryptocurrency rather than embracing the technology and building solutions/products on top of it.

There is only one bitcoin so don't keep on chasing for the next bitcoin. But keeping a large amount of bitcoins in your portfolio is still a good idea than choosing over altcoins which in the end have no definite values. There are a lot of altcoins today that have only ended as shitcoins so better make a wide research first before investing into such coins.

You should also focus on the concerning matter of how much an alt coin is popular and how much marketcap it provides to it's users.
You can still be thinking on investing into some alts which you consider having potential.
Nonetheless i know that Bitcoin only is the one "true" coin that will keep itself in a good steady value. Since it's the largest cryptocurrency being used for real life situations and not any other cryptocurrency.

The same thing happened to me in the past. Someone recommended me to buy a coin because its price is going to skyrocket during that year. So I bought some of that and waited. When times got tough he sold all his coins but recommended me to hodl it because there is no worry and the price will be up again soon. Unfortunately that didn't happened. Never listen to anyone without making your own research.

I think everybody aware about this, no one doing not buy and hold just bitcoin they are also hold others alt coins! no one can doing guess which alt can growing fast and run to highest value in near future, so you can buy and hold some of alt coins beside of bitcoin! I also prefer well rising alt coins and I love to buy and hold different alt coins and cryptocurrency beside some of bitcoins.

There is no "the next bitcoin" at this time.

What people currently seek is the "next best altcoin" like eth, dash, litecoin, etc.

a new crypto project that has the potential to be one of the top 10 coin or token.

I think the next big project that will be the next best altcoin are those with the best use cases to integrate the business side of things.
We already have enough platform coins (working and being developed) and these platforms are underutilized. True that we can't compete yet with transaction per second of Visa and Mastercard, but the business integration must happen for the blockchain and cryptocurrencies as a whole to be more widely adopted.

Remember, cryptocurrency is just one of the best application of blockchain technology.

Your suggestion is good but you can not push otherselves to not invest most of their fund in altcoin.actually I agree that there is no cryptocurrency that better than bitcoin, honestly I also ever invest more than 90% of my fund in a token but fortunately the token price has gone up then I sold all of that token for btc. I think invest in token for long term is risky but it is okay for short term investment. I always convert all of my token to btc so I always safe.

There is a reason other cryptos are tagged "altcoins" (alternative coins) while Bitcoin isn't yoked together with them. It's simply because Bitcoin is on a class of its own. There won't be another Bitcoin. A worst case scenero is that we get another coin getting a higher price than Bitcoin but that still won't make it Bitcoin. Bitcoin is a phenomenal and a pathfinder, not an imitation of any coin.