toriyama did great job transmitting goku's anger here.
another thing mentioned here, is goku saying that the reason the sayans were killed because they killed innocent people. frieza maybe saying "they died because i killed them", but it's not right. goku do believe that the sayans just got what they deserved for being bad, freeza was just the sender of the evil. the fact that freeza is deserves to die now however, because the cycle of revenge is repeating in the world. goku doesn't feel sad much about the sayans being dead, but the death of kuririn, which died 2nd time now, and his friend for 300 chapters now, is just making the sayan revenge back to freeza, continuing the "sayan pride" vegeta left him.
in short: the sayan deserved to be dead because of they was bad. frieza was only the deliver, but he deserves it in the same way, with the other way around, which goku the pure sayan survivor to finish the cycle.
toriyama is genius, periot.