First of all, tentacles were the most common symbiote ability.
It was similar to how humans could run, throw things and jump; they might not be good at all of them, but they could still do it.
As for the side effects of the tentacles, it was like the difference between a marathon and a sprint or between a dart or javelin.
Secondly, some symbiotes were more resistant to fire, ice, electricity or vibration, and some could launch special attacks. This was a rarer talent.
Luke knew why Gold Nugget liked to talk about its cloning ability; it was what differentiated it from other symbiotes.
Apart from that, the dog head's abilities were mediocre.
Even though to Luke, Gold Nugget being a "good kid" was a strong point, it was useless to the symbiote.
It was just like how animal protection couldn't be considered an ability, but just a type of trend.
But that was also why Luke regarded it as a reliable partner.