I have around 2k USD of btc and I wanted to swap it for something but I can't decide whether to buy eth or Solana both seem extremely promising in the far future.
Let me advise you as though I was the one who wanted to swap my Bitcoin for altcoins.
First, none of Ethereum and Solana will be my choice at this point, they've moved too high already. And for the record, I do not know the reason for liquidating Bitcoin for Ethereum when the two are moving with almost the same magnitude and percentage when they depreciate and appreciate in value.
Still, I may consider Solana because it is gaining more traction than before due to its upgrade and scalability, and it is now a better rival to higher cryptocurrencies. This may make it move more than expected. In the absence of that, I prefer a lesser-value coin/token which may still surely move at least 10 times the present value. On the contrary, with the present statuses of Ethereum and Solana, they can't achieve that in this bull run anymore.