I think very highly of Buddy. He is currently 4+17 for me. His attack power isn’t any great shakes, but he’s 5* sturdy, and the minions and debuffs are very powerful. He is better than a RP in that his effect includes an attack debuff too, but worse because of the short duration of the def down. You can be sloppy in timing with RP in a way that just isn’t as effective with Buddy.
But…if you put Buddy between squishy heroes, his minions give them better survivability, and his attack debuff magnifies this benefit. Drop Buddy on a sniper about to fire, and the benefit is huge. He would be (and, in fact, was) my choice out of those options.
Gad is basically a mini Ares at slow, and I know @BarryWuzHere uses him for blue titans. For me, he acts as a secondary healer in AW. I’m quite happy with him in this role.
LJ has very good tile damage and a decent effect, but I’m not partial to slow heroes, particularly ones who are glass cannons. @zephyr1 can speak a lot more eloquently to his virtues than I.