Stromer st1 diy build

I have a stromer st1 wich I want to use with my own battery, controller, motor and screen.
It has a 9 speed in the rear

The original tought was a 1500w voilamart or pasion ebike kit.

The rear dropout opening is 150, 151mm

If I search for a motor for a dropout for 150 i find the qs 205 v3.

No I can buy a second hand set nearby my home.
Qs 205 v3
72v sinewave controller 60a continuous
72v 25ah battery pack

No my question is. Isn't this to much for a ebike?

What do you guys suggest, i'm a newby.
I just want a reliable ebike with spare parts that is payable, not the stromer monster money parts.

I drive daily 2x 35km to work, only straight, no trafic.
Continues speed of 50 55km/h continues for an hour straight is ok.

I really would appriciate some kind of knowledge from this forum
Thanks in advance

135mm to 150mm isn't a big deal IMO just use some washers to compensate.
And yes, for your use case the the QS 205V 3 is too much if you aren't looking for trouble :lol: