My prediction is that the Caps will go with 14 forwards and 7 defense. This strategy would save a forward from going through waivers and almost likely being claimed. I am thinking in the shoes of Lavy, not myself here.
Reasoning:
I think McMichael secured a spot after last game. Snively has looked very good and losing him to waivers would be tough, especially since he is probably Sheary's replacement next season. AFJ has already been taken once, and his penalty killing is very very solid (which separates him from the likes of Leasson, Borgstrom, and Protas). I think Protas made the case to secure a spot, but he is waiver exempt, which will come in handy when injuries occur.
In terms of defense, Irwin provides a sense of security for Lavy. Unfortunately, I think Johansen gets claimed. If it were me, I think Johansen and Irwin played pretty similarly this preseason, and I believe Irwin would not get claimed, but Lavy is probably thinking comfortability for this year, in case of an injury.