And thats the problem! The upgrades the you're lacking is the main key on boosting your power. :D

Use your coupons for refines and have all your equips atleast refine level 4 and your main is atleast level 5, make your tactics atleast at level 3, be sure to have your item purified atleast with purple stats, make your main line up with mood atleast 25% and your main with atleast 45% mood stats, make sure your battle armor is upgraded too to the highest upgrade you can get, also check your summon cultivations as it also increases your power even it only increases in small number but every +1 counts, make sure your ninja bonds at home interface is always checked up use your extra coins to buy gifts and give the gifts to the ninjas you always use on your lineup, also spend coins on doing some eight inner gates and beset each rune according to your ninjas needs and do upgrade those runes as much as possible you can, check your charms to be sure to make all your equipments to alteast charm lv4 and beset a rainbow magatama with atleast level 4. And last but not the least, the magatamas, the rune stones, the runes in summon interface, be sure to always upgrade them.

And that's all what i did with my character, and it boost my power so well.