Bob Proctor: From a purely technical point of view the Point Saver with a stock coil will give you the biggest bang for the buck (literally).
It is not necessary to eliminate the points, and there are reasons to keep them. As one old hot rodder noted, points allow one to "adjust" the amount of spark the engine sees: close the gap and get a "longer" spark; open the gap and get a more "focused" spark. The timing of the engine is dependent, to a certain degree, on the point gap. For an expert tuner, this is an advantage; to the average tinkerer it could present an additional challenge. You decide.
Some would say a coil is a coil is a coil, there really isn't a whole lot of difference between them, except that some have the required resistor installed inside them, and some have the resistor installed externally. The main thing is not to run a coil without a "ballast" resistor. That being said, some coils are manufactured to higher quality standards and there are subtle differences between them, so that while a substitute may work OK, the "right" coil will perform that much better.
I would start with the Point Saver and if you want to show off the Bosch Blue go ahead; your point should last a loooong time with the Point Saver because the current is greatly reduced.
On the other hand, if you just don't ever want to mess with it again, go with the Point Slayer, you'll never have to adjust points again or worry about your timing.
I can't speak to installation issues, as I haven't made either upgrade myself. But I would check on what it will take to install each item before I made a decision.
I've pretty much decided to follow my own advice, I plan on getting the Point Saver for my 149 when I finally split the tractor to do the painting. I'm undecided about the Bosch coil.