Hi Acdii,
I think the Vectric Cut2D would be a good choice of CAD/CAM software (as are all the Vectric products).
Mach3 or Mach4 would be a good choice for controlling your Sherline and if you search the forum you will find many examples of others who have converted and successfully used their Sherline mills for producing model components.
I think your new laser machine would be best left controlled with it’s DSP controller. These use HPGL code rather than Gcode and CorelDraw is probably the last stronghold for the HPGL so it generally has to be used in preference.
I use Mach3 (and sometimes Mach4) for controlling my Milling machine, my Router machine and my Laser machine. You can read more about my laser in this thread;
https://www.machsupport.com/forum/index.php?topic=12444.210(The thread is now too long so perhaps just scroll through looking at the images and if there is anything of interest stop to read).
Tweakie.