Our DS is 24m, some similarities, had a hard start with slightly preterm birth, 3w in hospital with severe jaundice. All health trauma they go through leaves a mark on their development. Our son has SPD (sensory craving), and speech/communication delay, but (like your son), loves other kids, is not stuck on routine, engages ok.
Don’t think your son will be diagnosed with autism, as he has no social issues or repetitive behaviours. That’s my opinion. He obviously has speech delay, but well over half of kids with speech delays turn out to be normal kids.
My advice is to start private speech therapy. We have a session with our speech therapist once every 6w, and then we work with our son at home, following the tasks we are given. The results are quite good. Although he is still delayed, it is less than before. His eye contact has improved heaps, much closer to normal. Even crèche said eye contact is good. We also taught him to point. He is now occasionally joining two words , like “yellow car”, etc. He tells us when he wants something like “water” “open” (to open a box or bag of food”),… Your son can be taught all of that, too. We started the therapy when he was 14 months. At the time, everyone told us it was too early, but it paid off big time.
Another hint for you, while your son is learning things, pay attention to his learning curve. For example ,autistic kids would forget the words and have to re-learn them, they literally drop the words they just learnt, while normal kids would learn new things, have a plateau for a while, then learn more, then plateau, then learn more, etc. Our therapist, which is truly brilliant and respected in his profession, told us that. Also, keep on mind that some early ASD diagnosis are not correct, some medical studies show anything from 5%-20% misdiagnoses with kids under 4 years of age. The reason being is it is hard to assess the social component of development until that age.
Hope this helps.