Seeing as there is no solution on the horizon for the congestion on the Bitcoin network,
even if this were true, you still have a better "portfolio" with only bitcoin 
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I want to diversify my portfolio into some crypto currencies that are more scalable.
if you want profit since you are calling it portfolio then all the altcoins are viable options, and scalability of them is irrelevant.Quote
I wonder which altcoins have the highest transaction capacity.
there are a lot of altcoins with faster block generation (which is causing lots of other troubles by the way) but it has some more "capacity potential"!closest example: Litecoin
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I also wonder how Ethereum and Dash specifically would do if they had the number of transactions that bitcoin has x 10.
i also want to know this also would love knowing how they are going to handle the big size of their blockchain after 8 years when it was x10