Hello Richard and welcome. You will doubtless get many opinions on the tooling, a lot depends on how confident you are at making your own cutting tools and if you have a grinder for resharpening. If so then I would go for just the ready made tools that you need and add to them as the need arises.
Otherwise, the carbide inserts mean that you don't have to worry about resharpening and they are likely to last a long time on the materials normally used in model engineering. Again, I would only buy what you need immediately.
There are different types of knurling tools, one relies on exerting pressure against the spindle bearings and these I would avoid. The other type relies on exerting the pressure via a thumbscrew and put no pressure on the spindle
bearings, this is the one to go for.
Did the lathe come with chucks?
Brian