Please state your "High" RPM how high was it? It stuck for a while because of CVT do not have any gears and will stick at high RPM to get more power in return.

Below 2 is totally ok in my opinion especially from a stop. Although I never had any of Perodua's CVT Vehicle but I have driven a few Torque converter based CVT before.

From start usually will rev a little high and then it went down after going beyond 20km/h

The initial higher rev is to get more power at the get go because that's how CVT work, it will use the short ratio to push the car going.

However for point 2 and 3, this would need other owner to clarify, little jerking I think should be fine and expected at stop go speed.