I find this discussion fascinating. In these parts,(South Africa) there is only one approved way to join the pattern at an untowered field.
Overhead 2000’ AGL, 1mile past the runway turn to enter a descent on the ‘dead side’ i.e the side that is NOT the downwind leg (this may require overflying the runway again depending on your direction of arrival). Descending to pattern altitude turn crosswind, cross the extended centerline and then normal downwind and base.
No 45deg, no teardrops, no straight ins in the regulations.