I don't have anything like the experience of some of the contributors to this forum, but FWIW...

I use Vectric VCarve for most of what I do, and like it a lot. It's really easy to use once you have got used to it, which doesn't take long, and it is really good for things like lettering. I've been cutting some small printing blocks for my wife this evening, and VCarve does a good job of squaring out corners rather than leaving them at cutter diameter. It has some simple CAD (as long as you can do what you want with circles, lines, and rectangles) which is also quite useful for the odd quickie. I'm sure that there are some features that it doesn't have as it all seems deceptively simple to use, and powerful tools usually seem to have a really steep and long learning curve, but if it does what you need... If I were making flat plates with lettering and relatively straightforward holes in them, then VCarve would probably do the job pretty well. It ain't cheap, of course. There are probably other toolpath generators that would do all the things that VCarve does, but I'm not sure what they are - I have played with a couple of freeware tools (limited and fiddly to use) and took a look at Cambam, but plumped for VCarve in the end.
I get the feeling that I am in the minority on this forum because I'm a LinuxCNC user. Whenever machine control software is mentioned, it's almost always Mach3. I originally chose LinuxCNC because I was trying to build to a budget without committing too much money until I got a feel for this whole CNC thing. In the event, that's not what happened but I did use LinuxCNC because it was free and I didn't need another Windows machine/licence - it runs happily on an old PC that I had spare. Again, FWIW, it does everything I need, at least at the moment. Somewhat surprisingly, what it doesn't seem to have that Mach3 does have is a large amount of add-ons easily available (although at a cost in most cases, I think). I had rather naively expected that since LinuxCNC was more-or-less public domain, there would be a lot of extras available but that doesn't seem to be the case. Maybe I'm just looking in the wrong place! For example, I have been thinking about a touch probe for tool height setting, and it looks as if that is quite possible to incorporate but needs a bit of fiddling about to do. With Mach3, you just buy something that someone else has already written and is well-proven.
As far as CAD is concerned, you use whatever happens to suit you, I think. Sometimes I use TurboCAD (because I've been doing odd drawings in that for years), more often these days I use Rhino which is a pretty fearsome but very powerful 3D drawing tool, but for the stencils I cut the other day in 6mm ply, I was given scanned images in jpeg format and I ended up using Adobe Illustrator to turn those into vector format. Anything will do, as long as it gives an output format that your CAM package can accept. Most things seem to be happy with dxf, for example.
My machine is probably about as bendy as they come and still be usable, so if I can cut hardwoods, birch ply, and so on I'm sure that you will be OK for what you are planning to do with Traffolyte. Good luck!