ECDHE_RSA_WITH_AES_128_GCM_SHA256 is the cipher that corresponds to "TLS 1.2, RSA with ephemeral Elliptic Curve Diffie-Hellman, AES with 128-bit key in GCM mode, AEAD". RSA_WITH_AES_128_GCM_SHA256 is very similar, but uses RSA instead of Elliptic Curve Diffie Hellman for key exchange (see the list of supported ciphers).
However, specifying TlsCipherSuite.All should not take longer time to negotiate - the TLS server chooses a single cipher each time and there is no additional overhead. If might be interesting to try connecting with ECDHE_RSA_WITH_AES_128_GCM_SHA256 to see whether it takes longer as well (in general, ECDH key exchange should be actually be faster that RSA key exchange).