I'm not a professional, or a very competitive player, but I'm going to try to be more competitive. In melee, I loved Samus, she seems good in Brawl and similar, and the additional Zero Suit seems helpful. Samus is good because you will either love her for her projectiles (ranged attack), her combat attacks, or both like me. I think most people like her purely because they like her specials and her projectiles, but I like her combat more, like aerials, smashes, etc. I especially love her down air move, it's a great meteor smash, also her back air is a huge back kick that sends 'em flying, so I like to down air them off the ground, jump, and then back kick them. She also has good moves that build up damage well, like her up smash, her up air, and her forward air which give multiple damaging hits. Her specials aren't the deciding factor for me. I usually use her charge shot (B) only in friendlier matches, or only after I've killed off the top and have time to fully charge it. But I usually don't successfully use it. But, I can do some...mindgames? with the charge shot, especially in friendly games, or against another samus. I'll start charging the shot and release it about 4/5 of the way through, so they aren't quite expecting it. For projectiles though, I use her missiles (-> B) much more, sometimes with a charge shot as well. One thing that I've done a few times is made someone dodge a missle at a bad time so they fall to their death or I can easily kill them. Her bomb ( \/ B) is useful in a couple ways, I mainly use it to change my falls, I don't really do bomb jumps, I never really have to use it for recovery, but if I know I could recover or I'm falling, I can use my bomb to stale the fall, making it harder to combo me, or edge-guard me, it makes it harder to expect my timing, which to me is everything in this game. They can also be used in 4 player smashes, if there are multiple enemies close together, and focused on each other, I can quickly go in the middle and plop some bombs around, quickly adding some damage. After that I usually break them up with my screw attack ( ^ B). The screw attack is good to use in recovery but has a slow fall, leaving you open if you do it above land or offensively, so I rarely use it offensively unless its a 4 man brawl. In brawl her final smash looks awesome, and hopefully Zamus is good as well, her aerials seems good, but her specials look a little weak. Hope this helps you.
EDIT: I forgot to talk about her grapple beam, in the next game it may be better, but in Melee I almost never used it, because it was too unreliable and seemed to miss too often especially when I was close to the target. Her back throw was good, but I didn't do it often because it was too hard to grab, but don't let that discourage you.
