I have had an on again off again relationship with Sentinels. At first, last year, I loved them. They were everything iconic superheros like The Human Torch, Ice Man, Iron Man, etc, should be. Tough, Ranged attacks. Then I found their damage lacking the higher level I went, until at Incarnate I was somewhat disappointed. I was expecting Ranged Scrapper and got more like Defender Damage Plus. Now, they have again become one of my top favorite ATs (along with MMs and Controllers), as I've learned more about how to slot to squeeze out a little extra damage (but I'm not into heavy proccing), and I also tempered my expectations and learned to enjoy the concept and the playstyle, which i really enjoy. Fly, blast, move on., fly blast... At the end of the day, the game isn't that hard that a class in need of a little smidge of love is unplayable, so long as you put away the measuring stick vs. blaster and stalkers. So I agree with you. Sentinels really give you that 'feel like an actual super hero' experience.
BTW, I play with a buddy who is Energy/Energy and he's really good with his KB. There's a real difference between folks who know how to use it and have practiced, and those who don't. Just like with Hurricane/Storm users, you can easily tell the skilled from the unskilled. 🙂