Increasing the width was a good start, but the low duration doesn’t allow strategic use. The base duration should be 10 or 12 (!) sec and the ironbark talent should double it.
I imagine the main usage would be to create a line from 2 ults in open fights preventing to be surrounded. With long duration this would be actually a help. 10 sec is not enough.
Nobody uses ironbark thicket, because it’s still weak. One guy used it a few weeks ago, I was curious if my presumption is true, so I paid attention. It is.
The base ult is probably the worst in the entire game.
Tests would be needed to find the optimal duration ofc.