1). Kushimaru, Jinpachi, Jinin, and Sasori are the primary ninjas in that treasure that are effective. The only issue with that treasure is that they aren't meta shifting ninjas in my eyes. They'll be a thing but if you aren't a lightning or earth main then they wont benefit you. The main goal you want is to have Kurama link Naruto, Roshi, Killer B seven swordsman and preferably earth main. This is an example of an endgame meta. Seven swordsman do well damage wise I haven't seen them in any spacetime matches in a good while. A lot of people want this treasure rushed but it is a bit underwhelming imo. Once you get Madara or Kurama link you wont use any of the other ninjas because they don't work well together.

2). This one is tricky. Simply because they aren't necessarily blitz but have good damage output. I think they perform better in bond arena if I'm being honest. If I can dig up some GNW content on the seven swordsman Ill post it here. Sasori is the one that is a war ninja just because of what he does for you teammates. He plays a strong support role and revives (think of cross field earth main cleanse mystery). Roshi will always be in meta and he will be as monsterous in the future as he is now.

3). Now it is up to you but I advise you have Roshi on hand. 3rd raikage is also a decent option (only if you play earth or lightning).

If this didn't help, just stack scrolls. Ac*ulate free pulls in treasures until GNW drops then make your decision.

P.S.- Lastly, in arena for six paths, team comp in arena will take you further than outspeeding someone. If you have lower initiative in arena just play smarter and wait until they use their mysteries. Most people who are faster just fire off mysteries and don't wait to counter yours.

Best option currently is to type in "Fu Kenson treasure pull cap" on youtube. He covers the necessary scrolls it takes to pull ninjas from the treasures. ***I should add that the ninjas in the earlier treasure Sage is slightly different (nonexistent as they merged it with tendo +extra legendary ninjas***Tobirma & Tsunade 5th). Edo is also split, so you should ignore that atm. GNW is accurate. As for a list of skills for each of those ninjas you'll be better off looking on the *qq Chinese simulator. If you can't find either I can link both for you.