OpenSSH 5.2 switched to preferring AES-CTR.
OpenSSH 5.7 added ECDH as a kex and ECDSA as for signing.
OpenSSH 6.2 added encrypt-then-mac and prefers it by default.
OpenSSH 6.5 added Curve25519 as a kex and chacha20-poly1305 as a cipher. As well as Ed25519 for signing.
OpenSSH 8 will add quantum resistant algorithms for key exchange.