I think 3:24/3:25 and between 12:30 and 12:40 is reasonable to hope for now. Of course, it's quite possible that he could run even faster. Even I didn't expect him to do as well this season as he has. Also, if he has a long career, he could be 'in his prime' around 2026 or even 2030. Who knows what improvements to shoes, tracks etc will take place by then?
I also think he can run some seriously fast 800 times one day. Maybe he will be like Aouita and want to win medals and break records at 800 to 10000 and even beyond?
It seems funny now people are saying that he only gets by on his kick in slow races. Before this season everybody was saying his problem was an inability to kick.