From my point of view blockchain and coinbase wallet charges less charges fee and they are used by many peoples in the world so i would also suggest you to use these wallets for storing your btc and eth and these wallets are also offering to store eth and ltc in them.
You might be true that blockchain.info has lesser transaction fee because there are too many issues that some users use the regular fee to send but sometimes it when processed the fee takes too low mostly 1-50 sat/byte which will the transaction confirm too long and might be drop by the network because of lower fees.