There is a lot more wrong with those cuts than heights.
The way I see this tree....
The left is the smallest. Thinnest AND shortest.
You could make the middle or right trunk the dominant one.
Right would look silly so middle is dominant, the tallest and thickest.
The most important thing to consider before cutting for heights(the easy part), is getting the girths right before cutting anything. Otherwise you chase your tail to design demise.
The problem with these cuts is they pay no regard to any bonsai design aspect whatsoever.
The purple is the segment length proportions we shoot for. Long Medium Short. LMS.
These cuts have a Short Long Short.
A Medium Long Short.
And a medium medium medium.
It doesn't even make enough sense to get into trunk heights girths or placements.
It's essentially ruined. I mean, sure you can "start it over" from there, but it's a like a human voluntarily going into a coma for 5 years. Why do that to a tree?
I'm talking about growing this out almost as is, until that left space between trunks one and 2 close. Quite a bit thicker. Hopefully managing to make the sizes good and different with leaf pulling. Allowing you to make all the chops at the same time.
There is a "leave it taller" route. But I think there is material better suited.
Your initial cut lines, had 2 trunks about the same height.
One other word of caution, that big branch on the right trunk, is going to get that trunk bigger than the middle fast. It should be cut off, or addressed at least, depending which you want to be the dominant trunk.
Sorce