First, hugs. I love when newer members because interested in war. This was me a long time ago, except I was more of a noob
I will second that. Not that dd was a noob; the other part.
The roles in War 5 were mostly strategic decisions and were not even tied to specific players. For instance, you might be an Assassin in one round and a Scout in the next. I enjoyed this aspect of War 5, but I cannot yet say for certain if or how it will work in War 6.
As for the Strategist, I expect it will change since I doubt much, if any, vault work was actually done by the Strategist role.
As ddevans said, few victories are earned through player skill, so do not let a lack of experience dissuade you from applying for future Wars. If you are willing to commit to the event and contribute what you can, you can be a valuable asset to a team.