Better maneuver nodes

[viktor19]

I was wondering if there's a mod that takes the TWR of a vessel into consideration, something like what Principia does in it's flight planner. 

While sending a flyby probe to Eeloo in my 64K career, I had difficulties estimating the ∆V required and the ejection angle after maneuver since my stage had TWR of just 0.3. This would be great for ion and nuclear vessels. 

If it doesn't exist, could it be made? Is it hard to implement?