What settings are good is as Gerry said depends on what you doing, because you define the size of path error you want to allow.
So, you have to set the values according the tolerances you want the software to allow on the workpiece.
In most cases the higher tolerances will finish the jobs faster, because with the higher tolerances you give the software more freedom to optimise the path execution for lower speed,
because the software can go off the path more in order to make the path shorter and more optimal for speedy execution.
The tighter the tolerances are set the more closely the software has to follow the path, so then it has less freedom with the path optimisation, because it has to follow the path more closely.
So, the optimal settings depends on if your job needs more accuracy or higher speeds, there is always a tradeoff between these two.
And there is a description about the meaning of the parameters in the UCCNC manual, please read that to get a better understanding of the parameters.