The vast majority of people could care less how long or short you daven. Daven at whatever speed you want. These days, its not even considered kovodik to daven long really. Unless you make the minyan and are delyaing people just do whatever you want.
The only time I have an issue is if someone davens a 3 min S”E b’yochid and a 15 min one b’tzibur. Such a person must think people will respect him more for davening longer, which they dont. They dont care.