Astra has about 1 blueberry on them (I forget her exact height I just know it was 5 something. Little more than 5'2)

Was it 5’4?

Idk

Mine has several forms
When in his own lil universe (basically a random place he goes when bored and where he makes entire systems just for the fun of it) he can choose what size
In canon form, about 6’ 2 when standing
(He does not use his universe for combat or other purposes, it is just something he does for fun)

headcanon but

Half of the time Astra feels like she's tall because she spends a lot of time around Data and Ove

The other half the time she feels tiny because of Terra and Collector

Data would be more neutral because the height difference is pretty small