I owned a Vector too and used to look often at the ascent speed while hiking, since that gives you an idea on how fast you are going and allow to estimate the remaining altitude difference to your destination. Since the Vertical/Race watch family can show altitude and barometric pressure, they could easily display also the vertical speed as a complication, it’s odd that isn’t present as a choice.
I agree with you about the ridiculous small font of the time field shown on the top of the activity fields, it’s actually useless, especially while in outdoor activities.