I have experimented with voice telemetry over several years now and 'as we all do' started with it telling me everything every 20 seconds or so. Soon switched it off! Even I got fed up with the constant 'Babble' which was often many seconds out of date as it joined the digital queue for voicing.
However, I find that different model types benefit from different messages. I often set an over 400' alarm (in models with telemetry) for models over 7kg when flying in areas that restrict height e.g. FIR or restricted airspace, not our field because it is NOTAMed as higher. The two main things I find really useful is regular voltage readouts for the motor LiPo on electric models, to prevent over discharging or that rapid power fade at the end and the Time to Go on countdown timer readout (usually every minute) when flying turbine models, which prevents eyes being taken away from flight observation to alleviate estimated fuel remaining anxiety!!!
The alarm function is good for things that are really difficult to judge accurately, which is not usually speed as we have all become quite adept at this, more by how the model 'feels'. However, height and distance can vary significantly with different model sizes. I am a trained Met Observer who has been judging height of cloud for most of my Air Traffic Control Career and found I was way out on model height, once I had something to measure it with, we fly a lot higher than we think!