That's good that your group is working on it, but that's probably the reason if you're comparing yourself to people of the same level from higher groups (my group is about to be level 9, group skills will increase to 45 shortly after). Well, I was just using Akatsuki as an example, but a 5-star ninja you can grind is better than 3-star of one you can't, for now in terms of battle power (I run 4-star Tobi and Kakashi, 2-star GNW Neji).
You definitely don't want to just fight exam 80 head on. I used Fire main, Ino, Neji, Kakashi. You basically will make Sasuke kill his own team, and permanently control him as well. What do you mean you're not using them? The runes on summons you don't use, still give you stats.
If you're free pulling, it'll only be a matter of time before you get a designated rare of that treasure. It's like refinements and although I don't know the specific cap (or if there is one), the average is 40-60 pulls. What I meant regarding your group was, talk with your entire group and see if they want to join a bigger group altogether, otherwise, start recruiting :P.