The starting and ending points of the line are dark

The challenge will be in mitigating this with your 80W tube. Your laser likely won’t fire reliably much below 10% power and your machine acceleration configuration likely isn’t sufficient to avoid the burns.

I’d suggest running some test to see how low of power you can reliably run. If you can get it low enough to avoid the burns using that value as min power then great. Else, you could try tuning your acceleration to see if there’s any headroom there without losing steps. Between a low enough min power and acceleration changes you may be able to get there.

Having said that, this is a problem I’ve never solved on my 80W Omtech with min power alone granted I’ve never put a lot of time into this.

Another consideration, while you may be able to solve the problem for this particular design that could be insufficient for other designs if those have higher acceleration/deceleration demands.