Ethereum is the only sensible alternative to Bitcoin but Ethereum has major scalability issues and much less infrastructure compared to Bitcoin to alleviate those issues.
Proof of Stake is coming which helps a lot with overall effort expended, if not directly tx/s.
What does Bitcoin have that Ethereum doesn't for scaling transaction rate?
That said Ethereum would be a reasonable alternative, but in terms of stability and performance, Bitcoin is far ahead of Ethereum currently. Maybe Ethereum 2.0 with sharding and staking solves those scalability issues and at that time it will be the best choice, but right now there are too many unknowns.
USDC also uses Algorand, Solana and Stellar: