Expand stroke is not working well

[peacemind]

 

I am new for affinity designer.

I use tablet pen to draw flower with normal pen brush when I finish I would like to expand stroke to a shape but when I do it it not look same as I design before expand stroke

I spend huge time to draw a lot of flower but when I expand I not same as I design. So disappoint for first time use.

How can I fix this issue? 

 

 

[peacemind]

Thank you for reply

I try to do with suggest in link post. That if I set variance to 100% and expand stroke the shape almost the same thick as original

but sometime I just do not want end of my line is to thin when set variance to 100%.I usually use variance 75% 

and also I try to use pen tool that not got this issue.

But I use vector brush tool to just draw and it make more time process if I have to adjust every line pressure curve when I draw
On iPad app also have same issue

I hope affinity team to fix this issue both on iPad app and desktop app