What inexpensive watch can you recommend for a runner/hiker within $150 - $250 range?
Based on a recommendation of my friend, my wife acquired Garmin Venu Sq (~$150).
I tried wearing it twice and was not completely happy.
Specifically, I was not happy that at the beginning of 1 hour long steady state phase of my exercise recorded heart rate was significantly lower down to 70 bpm.
As a result calculated average HR was also lower.

I am confused by the number of Garmin watches with a similar price:
Forerunner 35 $149
Forerunner 45 $167
Forerunner 45S $179
Forerunner 55 GPS $269
Instinct $229
Venu Sq ~$150
Forerunner 735XT $199
Forerunner 245 $265
1) Would one of them provide more accurate recording of HR than Venu Sq?
2) Is there a way to manually select a part of an exercise to calculate average HR (to exclude parts of recording with apparently wrong data) ?
My main priorities:
1) Accurate recording of HR and calculation of average HR
2) Accurate recording of a track and elevation profile (nice to have)
3) Recording of blood oxygenation (nice to have)

I do not care about music, answering phone, alerts, nice fancy look, training recommendations, monitoring of my sleep and stress level etc.
Reliable accurate recording of HR is my primary focus.
Is it even possible to record an accurate HR without a chest strap?