To the OP, check the videos MR Slin made regarding medic advice.
Dave_the_IrateThe top tip I've been giving to medics I've mentored (newer comp players):
During an uber, once you only have ~50% of your uber remaining you need to think about your post-uber position
.
If not arguably before you even uber too, since that factors into the decision making about why you are actually using an uber and what you want to achieve.
Of course, what you plan on doing can change during an uber depending on how it goes, so what you said still applies.