Howdy Speedy - haven't seen ya around much lately.
Yes I think it is a good idea to have more valuable coins slabbed. It offers excellent protection and will help you learn. It also makes it much easier to sell your coins should the need ever arise.
I'm sure you already know - as Satootoko and many others have said - only use the top 4. And here I'm going to make a comment that most do not make. Use all 4 of the top 4. This will be very helpful, especially to those who are working on their grading skills. By using only 1 company - you become too accustomed to grading by their standards. And since they all have different standards - you do yourself a disservice by doing this.
Getting used to how the different grading companies grade different coins goes a long way in teaching you to understand not only the grading process used by each company but it also helps you have a more rounded understanding of the grading process itself. And pretty soon you find yourself questioning the grades assigned by the companies because you have developed your own standards - a composite standard if you will. Then you will realize that your composite standard allows you to pick the best of the best
This is when collecting really becomes fun - at least for me
