Immediate mode annotations with customized chart layout

Hello,

I need to draw a lot of annotations. Those are pretty simple figures/icons. The gotchas:

1. The axis (ticks/labels) should be inside of the chart area.
2. The annotation should be drawn on the border of the axis/chart.

I started to use the immediate mode for this. Was pretty happy to see there are Layers in the render context and I thought I could schedule or manipulate the rendereings when it comes to what I want. Unfotunately it is immutable.

The first thing I could come over by manipulating the template at runtime although I do not want to re-template it in fear of bigger template changes than the change of Grid.Row at runtime.
The second part is more tricky now. I would like to have fine grained control over the ordering of what is drawn. At least above/below the RenderableSeries but best to select the layers as wanted.

One big deal I did overcome is some mouse hover action for the drawn annotations.

So my idea now would be to add custom rendering layers like the HighQualityRenderSurface but I have no Idea how this impacts the performance. I already have a target of ~30 charts. Fortunately visible ones would be only around 8 so I could manipualte the visibility on scroll to prevent render.

I attached an example of the idea.

What I tried before was interfering with The ISciChartRenderer to wrap a before and after render. The problem is the Services are registered and the value is asigned to a property so that my re-register (swap) has no effect. Finally I got it working using a IAnnotationsDrawingProvider wrapper.

You can find the related post on StackOverflow:
https://stackoverflow.com/questions/78436617/immediate-mode-scichart-rendering-with-ordering-and-axis-positioning-custom-fas

EDIT:
For the fine grained control over the rendering order I managed to use the Layers just need to do it before any counterpart manages to schedule an action (ISciChartRenderer worked just the base class private variable assignment is nasty).