For one, I wouldn't follow that power menu at all. While it does show you some of the areas you are lacking in, it is heavily unreliable. *turn your attention to its recommended power* Now roll your eyes.

Now as far as power goes there are so any factors at this stage in the game.

1. Where are you currently in ninja exams?

2. What Level are your tactics?(needs to be at least lvl 4)

3. What are the level of your rune stones(cave keys)?(try to get level 5 on each ninja)

4. What is your rank is your battle armor and level at?(this varies but most people can obtain rank 5 rather easily now and should be lvl 27)

5. DO you belong to a group? If so are your group skills maxed out?

6. What are your refinements like?(should be using medium runes at this stage in the game, stack them through monthy)

7. What are your charm levels? (Work on ultimate training)

8. What level are the runes in your summon interface?(these should be at least level 4 or 5)

9. What level are your Magatamas?(for a good amount of power at least level 5's on each ninja. )

10. What are your inner gates like?(use the points for initiative runes in the shop. best value atm. Focus on baseline stats such as nin, life, attack, def, res)

Answer these questions, this is your prime source of power. Purifies factor in but wont help much unless you have good scaling on your rune stones I believe. Clothing affects power as well but you get a better benefit from it when you have more power. Also I failed to include ninja tools and nature stones. Once you get to the Susanoo brothers instance farm out the red tools and level them. Make sure to ALWAYS ALWAYS do TI. I believe you still get good power from tools. It used to give roughly 400-600 power on some tools. Also, don't forget to mood your ninjas, 25% is good if you ont plan to use them but 65% is a MUST on your main regardless of who you are using.

Lastly, to answer your question as to why some lower level players have high bp...it could be one of two things or both really.

1. They froze their level by not doing exp events. Ninetails, TI, or even doing the story missions. This gives you an edge in some areas such as Sage world. Ideally you freeze between level 60-70 to ensure you're on par.

2. They pay lol. Not much you can do about it except spend smarter.