The updated messages are clearer than the original ones in my eyes, excellent.

Though I could hack some fields to aggregate to run into the messages that have been changed here, to test, I didn't seem to hit them by ramping up the verbosity "to 11" (i.e. max debug/-1) on the aggregate test, so that suggests we can improve test coverage in future by including cases corresponding to attempted aggregation leading to these messages e.g. of fields where some have identical 1D coordinates, etc.

Also, during reviewing I noticed a few formatting errors in the higher-verbosity logging messages (probably mistakenly introduced by me during the original conversion from print statements), so I will put up a PR shortly in soon to fix those. I might also check all tests under debug verbosity to pick up on any obvious further log message issues towards that PR.